Clinical Focus

  • Radiation Oncology
  • Breast Cancer
  • Brain Tumors
  • Radiosurgery

Academic Appointments

Honors & Awards

  • 99th Annual Meeting Travel Award, American Radium Society (2017)
  • Poster of Distinction Award, American Radium Society (2017)
  • Roentgen Research Award, RSNA (2017)
  • Malcolm A. Bagshaw Award, Stanford Radiation Oncology (2016)
  • KL2 Mentored Career Development Award, SPECTRUM (2015-2017)
  • 97th Annual Meeting Travel Award, American Radium Society (2015)
  • Merit Award, American Society of Clinical Oncology (2015)
  • Academic Distinction, University of Michigan Medical School (2012)
  • Glasgow-Rubin Achievement Citation, University of Michigan Medical School (2012)
  • Medical Honor Society, Alpha Omega Alpha (2012)


2017-18 Courses


All Publications

  • Reirradiation with stereotactic body radiation therapy after prior conventional fractionation radiation for locally recurrent pancreatic adenocarcinoma. Advances in radiation oncology Koong, A. J., Toesca, D. A., von Eyben, R., Pollom, E. L., Chang, D. T. ; 2 (1): 27–36


    Locally recurrent pancreatic cancer after prior radiotherapy is a therapeutic challenge with limited treatment options. This study examines the safety and efficacy of stereotactic body radiation therapy (SBRT) for locally recurrent pancreatic adenocarcinoma after prior conventional fractionation radiotherapy (CRT).Outcomes from all patients treated with SBRT for locally recurrent pancreatic adenocarcinoma after prior CRT at our institution were reviewed. A total of 23 patients were identified. Prior CRT median dose was 50.4 Gy (range, 30-60 Gy). Twelve patients (52%) had previously undergone surgery and received CRT as neo- or adjuvant treatment. Nine patients (39.1%) were reirradiated with SBRT with a dose of 25 Gy in a single fraction, and 14 patients (60.8%) received a 5-fraction SBRT schedule with a median dose of 25 Gy (range, 20-33 Gy) in 5 fractions (1-5 fractions).Median follow-up time was 28 months (range, 9-77 months). The median planning target volume was 46 cm(3) (range, 14-89 cm(3)). Median overall survival from diagnosis and from reirradiation were 27.5 months (range, 10-77 months) and 8.5 months (range, 1 month to not reached) respectively. The cumulative incidence of local failures at the last follow-up was 19%. For the 4 patients who presented with local failure, one was treated with a single fraction of 25 Gy, and the other 3 were treated with 25 Gy in 5 fractions. Three patients presented regional failure, with a cumulative incidence of 14%, all with concurrent distant progression. The cumulative incidence of distant progression was 64% at last follow-up. After reirradiation, 6 patients (26.1%) developed a grade 2 or 3 gastrointestinal toxicity, 4 of them occurring among patients treated with a single-fraction SBRT regimen.Our report shows that SBRT for reirradiation of locally recurrent pancreas adenocarcinoma is a feasible option with good local control and acceptable toxicity rates, especially with a multifraction schedule.

    View details for DOI 10.1016/j.adro.2017.01.003

    View details for PubMedID 28740913

    View details for PubMedCentralID PMC5514250

  • Newly diagnosed glioblastoma: adverse socioeconomic factors correlate with delay in radiotherapy initiation and worse overall survival. Journal of radiation research Pollom, E. L., Fujimoto, D. K., Han, S. S., Harris, J. P., Tharin, S. A., Soltys, S. G. 2018


    The optimal time for starting radiation in patients with glioblastoma (GBM) is controversial. We aimed to evaluate postoperative radiotherapy treatment patterns and the impact of timing of radiotherapy on survival outcomes in patients with GBM using a large, national hospital-based registry in the era of Stupp chemoradiation. We performed a retrospective cohort study using the National Cancer Data Base and identified adults with GBM diagnosed between 2010 and 2013 and treated with chemoradiation. We classified time from surgery/biopsy to radiation start into the following categories: <15 days, 15-21 days, 22-28 days, 29-35 days, 36-42 days and >42 days. We assessed the relation between time to radiation start and survival using Cox proportional hazards modeling adjusting for clinically relevant variables that were selected a priori. We used multivariate logistic modeling to determine factors independently associated with receipt of delayed radiation treatment. A total of 12 738 patients met our inclusion criteria after our cohort selection process. The majority of patients underwent either gross total (n = 5270, 41%) or subtotal (n = 4700, 37%) resection, while 2768 patients (22%) underwent biopsy only. Median time from definitive surgery or biopsy to initiation of radiation was 29 days (interquartile range 24-36 days). For patients who had biopsy or subtotal resection, earlier initiation of radiation did not appear to be associated with improved survival. However, among patients who underwent gross total resection, there appeared to be improved survival with early initiation of radiation. Patients who initiated radiation within 15-21 days of gross total resection had improved survival (hazard ratio 0.82, 95% confidence interval 0.69-0.98, P = 0.03) compared with patients who had delayed (>42 days after surgery) radiation. There was also a trend (P = 0.07 to 0.12) for improved survival for patients who initiated radiation within 22-35 days of gross total resection compared with patients who had delayed radiation. Patients who were black, had Medicaid or other government insurance or were not insured, and who lived in metropolitan areas or further away from the treating facility had higher odds of receiving radiation >35 days after gross total resection. Patients who lived in higher income areas had higher odds of receiving radiation within 35 days of a gross total resection. In a large cohort of patients with GBM treated with chemoradiation, our data suggest a survival benefit in initiating radiotherapy within 35 days after gross total resection. Further research is warranted to understand barriers to timely access to optimal therapy.

    View details for DOI 10.1093/jrr/rrx103

    View details for PubMedID 29432548

  • Survival Impact of Postoperative Radiotherapy Timing in Pediatric and Adolescent Medulloblastoma. Neuro-oncology Chin, A. L., Moding, E. J., Donaldson, S. S., Gibbs, I. C., Soltys, S. G., Hiniker, S. M., Pollom, E. L. 2018


    Radiation therapy (RT) remains a critical component of multimodality treatment for medulloblastoma. Traditionally, clinicians strive to start RT within 4-5 weeks of surgery, but the optimal timing after surgery remains unclear.Using the National Cancer Database, we identified pediatric and adolescent patients with medulloblastoma treated with curative-intent surgery, RT, and chemotherapy. Factors associated with early or delayed RT were identified using Pearson chi-squared tests. Overall survival (OS) differences based on RT timing were compared using the Kaplan-Meier estimator with log-rank tests. Patient, tumor, and treatment characteristics associated with OS were analyzed with univariate and multivariate Cox proportional hazard models.Among the 1338 patients analyzed, early RT (defined as initiation ≤3 weeks after surgery) was associated with younger age, M1-3 disease, and subtotal resection. Patients who initiated RT early had decreased five-year OS compared with patients who initiated RT 3.1-4, 4.1-5, or >5 weeks after surgery (72.5%, 80.5%, 79.4%, and 77.8%, respectively; p=0.019), but there was no significant difference in OS among the latter three groups (p=0.788). On multivariate analysis, early RT versus the 3.1-4-week interval was significantly associated with poorer OS (adjusted HR 1.72; 95% CI 1.19-2.48; p=0.004), while time to RT of >5 weeks but within 90 days of surgery did not adversely impact OS (p=0.563).In this large national database analysis, delaying RT within 90 days of surgery was not associated with inferior outcomes. Although clinical judgment remains paramount, postoperative RT timing should allow for healing and the development of an optimal treatment plan.

    View details for DOI 10.1093/neuonc/noy001

    View details for PubMedID 29309676

  • Gross total resection and adjuvant radiotherapy most significant predictors of improved survival in patients with atypical meningioma. Cancer Rydzewski, N. R., Lesniak, M. S., Chandler, J. P., Kalapurakal, J. A., Pollom, E., Tate, M. C., Bloch, O., Kruser, T., Dalal, P., Sachdev, S. 2018; 124 (4): 734–42


    Atypical and malignant meningiomas are far less common than benign meningiomas. As aggressive lesions, they are prone to local recurrence and may lead to decreased survival. Although malignant meningiomas typically are treated with maximal surgical resection and adjuvant radiotherapy (RT), to the authors' knowledge the optimal treatment for atypical lesions remains to be defined. There are limited prospective data in this setting.The National Cancer Data Base was queried to investigate cases of histologically confirmed meningiomas diagnosed from 2004 to 2014. This included 7811 patients with atypical meningiomas (World Health Organization grade 2) and 1936 patients with malignant meningiomas (World Health Organization grade 3); during the same period, a total of 60,345 patients were diagnosed with benign meningiomas (World Health Organization grade 1). Data collected included patient and tumor characteristics, extent of surgical resection, and use of RT. Survival analysis was performed using Kaplan-Meier estimates with the log-rank test of significance and Cox univariate and multivariate regression. Logistic regression was used to determine factors associated with use of RT.The 5-year overall survival rate was 85.5% in patients with benign meningiomas, 75.9% in patients with atypical meningiomas, and 55.4% in patients with malignant meningiomas (P<.0001). In patients with atypical meningiomas, gross (macroscopic) total resection (GTR) and adjuvant RT were found to be associated with significantly improved survival, independently and especially in unison (GTR plus RT: hazard ratio, 0.47; P = .002). On multivariate analysis, the combination of GTR plus RT was found to be the most important factor for improved survival. However, GTR was associated with significantly lower rates of RT use.GTR and adjuvant RT appear to be highly associated with improved survival, independent of other factors, in patients with atypical meningiomas. Cancer 2018;124:734-42. © 2017 American Cancer Society.

    View details for DOI 10.1002/cncr.31088

    View details for PubMedID 29131312

  • Normal Tissue Constraints for Abdominal and Thoracic Stereotactic Body Radiotherapy. Seminars in radiation oncology Pollom, E. L., Chin, A. L., Diehn, M., Loo, B. W., Chang, D. T. 2017; 27 (3): 197-208


    Although stereotactic body radiotherapy (SBRT) or stereotactic ablative radiotherapy has become an established standard of care for the treatment of a variety of malignancies, our understanding of normal tissue dose tolerance with extreme hypofractionation remains immature. Since Timmerman initially proposed normal tissue dose constraints for SBRT in the 2008 issue of Seminars of Radiation Oncology, experience with SBRT has grown, and more long-term clinical outcome data have been reported. This article reviews the modern toxicity literature and provides updated clinically practical and useful recommendations of SBRT dose constraints for extracranial sites. We focus on the major organs of the thoracic and upper abdomen, specifically the liver and the lung.

    View details for DOI 10.1016/j.semradonc.2017.02.001

    View details for PubMedID 28577827

  • Phase 1/2 Trial of 5-Fraction Stereotactic Radiosurgery With 5-mm Margins With Concurrent and Adjuvant Temozolomide in Newly Diagnosed Supratentorial Glioblastoma: Health-Related Quality of Life Results. International journal of radiation oncology, biology, physics Pollom, E. L., Fujimoto, D., Wynne, J., Seiger, K., Modlin, L. A., Jacobs, L. R., Azoulay, M., von Eyben, R., Tupper, L., Gibbs, I. C., Hancock, S. L., Li, G., Chang, S. D., Adler, J. R., Harsh, G. R., Harraher, C., Nagpal, S., Thomas, R. P., Recht, L. D., Choi, C. Y., Soltys, S. G. 2017; 98 (1): 123-130


    We report a longitudinal assessment of health-related quality of life (HRQOL) in patients with glioblastoma (GBM) treated on a prospective dose escalation trial of 5-fraction stereotactic radiosurgery (25-40 Gy in 5 fractions) with concurrent and adjuvant temozolomide.HRQOL was assessed using the European Organization for Research and Treatment of Cancer (EORTC) quality of life questionnaire core-30 (QLQ-C30) general, the EORTC quality of life questionnaire-brain cancer specific module (QLQ-BN20), and the M.D. Anderson Symptom Inventory-Brain Tumor (MDASI-BT). Questionnaires were completed at baseline and at every follow-up visit after completion of radiosurgery. Changes from baseline for 9 predefined HRQOL measures (global quality of life, physical functioning, social functioning, emotional functioning, motor dysfunction, communication deficit, fatigue, insomnia, and future uncertainty) were calculated at every time point.With a median follow-up time of 10.4 months (range, 0.4-52 months), 139 total HRQOL questionnaires were completed by the 30 patients on trial. Compliance with HRQOL assessment was 76% at 12 months. Communication deficit significantly worsened over time, with a decline of 1.7 points per month (P=.008). No significant changes over time were detected in the other 8 scales of our primary analysis, including global quality of life. Although 8 patients (27%) experienced adverse radiation effects (ARE) on this dose escalation trial, it was not associated with a statistically significant decline in any of the primary HRQOL scales. Disease progression was associated with communication deficit, with patients experiencing an average worsening of 13.9 points per month after progression compared with 0.7 points per month before progression (P=.01).On this 5-fraction dose escalation protocol for newly diagnosed GBM, overall HRQOL remained stable and appears similar to historical controls of 30 fractions of radiation therapy. Tumor recurrence was associated with worsening communication deficit, and ARE did not correlate with a decline in HRQOL.

    View details for DOI 10.1016/j.ijrobp.2017.01.242

    View details for PubMedID 28586949

  • Assessing local progression after stereotactic body radiation therapy for unresectable pancreatic adenocarcinoma: CT versus PET. Practical radiation oncology Toesca, D. A., Pollom, E. L., Poullos, P. D., Flynt, L., Cui, Y., Quon, A., von Eyben, R., Koong, A. C., Chang, D. T. 2017; 7 (2): 120-125


    Evaluation of local tumor progression (LP) has typically been defined by contrast-enhanced computed tomography (CT) imaging after stereotactic body radiation therapy (SBRT) for locally advanced pancreatic cancer (PDAC). The purpose of this study is to determine the benefit of adding 18F-fluorodeoxyglucose-positron emission tomography (FDG-PET) imaging to CT for LP assessment of PDAC after SBRT.We retrospectively reviewed pretreatment, follow-up images, and outcomes of all patients treated with definitive SBRT for unresectable PDAC between December 2002 and December 2015 at our institution. For each patient, we independently analyzed LP both by CT and by FDG-PET criteria, using the Response Evaluation Criteria In Solid Tumors version 1.1 and the FDG-PET Response Evaluation Criteria In Solid Tumors version 1.0, respectively.Among 206 patients treated with definitive SBRT for unresectable PDAC, we identified 30 with LP on follow-up. Four did not undergo follow-up FDG-PET. Median time to LP after SBRT was 7.5 months (range, 2-25 months). Of the 26 patients with LP who had follow-up FDG-PET, 21 were diagnosed by FDG-PET (80.7%), 14 by CT (53.8%), and 9 by both FDG-PET and CT (34.6%). Use of CT alone revealed only 53.8% of cases of LP detected when FDG-PET and CT were combined. The cumulative incidence of LP, based on competing risk of death, at 1 and 2 years after SBRT was 9.6% and 16.7% by CT and 11% and 29.1% by FDG-PET, respectively.FDG-PET increases the chance of detecting LP of unresectable PDAC after SBRT and can have an important impact on reported outcomes. We recommend obtaining FDG-PET to assess treatment response when evaluating efficacy of SBRT and taking its use into account when comparing clinical data.

    View details for DOI 10.1016/j.prro.2016.09.002

    View details for PubMedID 28274396

  • Patterns of Care in Adjuvant Therapy for Resected Oral Cavity Squamous Cell Cancer in Elderly Patients. International journal of radiation oncology, biology, physics Pollom, E. L., Chin, A. L., Lee, N. Y., Tsai, C. J. 2017


    To characterize the patterns of care and potential barriers to access to care for elderly patients with oral cavity cancer in the adjuvant setting.We performed a retrospective cohort study using the National Cancer Data Base and identified patients with resected oral cavity squamous cell carcinoma diagnosed between 2004 and 2012, who survived for ≥3 months after surgery. We used logistic regression models to assess the association between age (<70, 70-79, and ≥80 years) and the receipt of adjuvant therapy within 3 months of surgery. We additionally assessed the association between patient and tumor characteristics and the receipt of adjuvant therapy among those aged ≥70 years.A total of 25,829 patients were included in the study. Compared with those aged <70 years, older patients were more likely to have no neck dissection or have fewer lymph nodes dissected and were less likely to receive adjuvant therapy than younger patients. Among our cohort, 11,361 patients (44%) had pathologic T3-T4 disease or N2-N3 disease, and 4185 patients (16%) had extracapsular nodal extension or positive surgical margins. In multivariate analyses controlling for comorbidity and demographic characteristics, older age was independently associated with lower odds of receiving adjuvant radiation therapy in the subgroup with T3 or T4 disease or N2 or N3 disease and adjuvant chemoradiation therapy in the positive extracapsular nodal extension or positive surgical margin subgroup. Among elderly patients, both greater patient distance from reporting facility and older age were associated with lower odds of receiving both adjuvant radiation therapy (odds ratio 0.66; 95% confidence interval, 0.55-0.81) and chemoradiation therapy (odds ratio 0.56; 95% confidence interval, 0.40-0.79).In a national hospital-based cohort of patients with oral cavity cancer, elderly patients were less likely to receive adjuvant radiation or chemoradiation therapy. Greater patient distance from reporting facility, in addition to older age, was associated with lower odds of receiving both adjuvant radiation therapy and adjuvant chemoradiation therapy.

    View details for DOI 10.1016/j.ijrobp.2017.01.224

    View details for PubMedID 28366574

  • The Impact of Intensity Modulated Radiation Therapy on Hospitalization Outcomes in the SEER-Medicare Population With Anal Squamous Cell Carcinoma. International journal of radiation oncology, biology, physics Pollom, E. L., Wang, G., Harris, J. P., Koong, A. C., Bendavid, E., Bhattacharya, J., Chang, D. T. 2017


    We examined the impact of intensity modulated radiation therapy (IMRT) on hospitalization rates in the Surveillance, Epidemiology, and End Results (SEER)-Medicare population with anal squamous cell carcinoma (SCC).We performed a retrospective cohort study using the SEER-Medicare database. We identified patients with nonmetastatic anal SCC diagnosed between 2001 and 2011 and treated with chemoradiation therapy. We assessed the relation between IMRT and first hospitalization by use of a multivariate competing-risk model, as well as instrumental variable analysis, using provider IMRT affinity as our instrument.Of the 1165 patients included in our study, 458 (39%) received IMRT. IMRT use increased over time and was associated more with regional and provider characteristics than with patient characteristics. The 3- and 6-month cumulative incidences of first hospitalization were 41.9% (95% confidence interval [CI], 37.3%-46.4%) and 47.6% (95% CI, 43.0%-52.2%), respectively, for the IMRT cohort and 46.7% (95% CI, 43.0%-50.4%) and 52.1% (95% CI, 48.4%-55.7%), respectively, for the non-IMRT cohort. IMRT was associated with a decreased hazard of first hospitalization compared with 3-dimensional radiation techniques (hazard ratio, 0.70; 95% CI, 0.58-0.84; P=.0002). Instrumental variable analysis suggested an even greater reduction in hospitalizations with IMRT after controlling for unmeasured confounders. There was a trend toward improved overall survival with IMRT, with an adjusted hazard ratio of 0.77 (95% CI, 0.59-1.00; P=.05).The use of IMRT is associated with reduced hospitalizations in elderly patients with anal SCC. Further work is warranted to understand the long-term health and cost impact of IMRT, particularly for patient subgroups most at risk of toxicity and hospitalization.

    View details for DOI 10.1016/j.ijrobp.2017.01.006

    View details for PubMedID 28258896

  • Cost-effectiveness of Stereotactic Body Radiation Therapy versus Radiofrequency Ablation for Hepatocellular Carcinoma: A Markov Modeling Study. Radiology Pollom, E. L., Lee, K., Durkee, B. Y., Grade, M., Mokhtari, D. A., Wahl, D. R., Feng, M., Kothary, N., Koong, A. C., Owens, D. K., Goldhaber-Fiebert, J., Chang, D. T. 2017: 161509-?


    Purpose To assess the cost-effectiveness of stereotactic body radiation therapy (SBRT) versus radiofrequency ablation (RFA) for patients with inoperable localized hepatocellular carcinoma (HCC) who are eligible for both SBRT and RFA. Materials and Methods A decision-analytic Markov model was developed for patients with inoperable, localized HCC who were eligible for both RFA and SBRT to evaluate the cost-effectiveness of the following treatment strategies: (a) SBRT as initial treatment followed by SBRT for local progression (SBRT-SBRT), (b) RFA followed by RFA for local progression (RFA-RFA), (c) SBRT followed by RFA for local progression (SBRT-RFA), and (d) RFA followed by SBRT for local progression (RFA-SBRT). Probabilities of disease progression, treatment characteristics, and mortality were derived from published studies. Outcomes included health benefits expressed as discounted quality-adjusted life years (QALYs), costs in U.S. dollars, and cost-effectiveness expressed as an incremental cost-effectiveness ratio. Deterministic and probabilistic sensitivity analysis was performed to assess the robustness of the findings. Results In the base case, SBRT-SBRT yielded the most QALYs (1.565) and cost $197 557. RFA-SBRT yielded 1.558 QALYs and cost $193 288. SBRT-SBRT was not cost-effective, at $558 679 per QALY gained relative to RFA-SBRT. RFA-SBRT was the preferred strategy, because RFA-RFA and SBRT-RFA were less effective and more costly. In all evaluated scenarios, SBRT was preferred as salvage therapy for local progression after RFA. Probabilistic sensitivity analysis showed that at a willingness-to-pay threshold of $100 000 per QALY gained, RFA-SBRT was preferred in 65.8% of simulations. Conclusion SBRT for initial treatment of localized, inoperable HCC is not cost-effective. However, SBRT is the preferred salvage therapy for local progression after RFA. (©) RSNA, 2017 Online supplemental material is available for this article.

    View details for DOI 10.1148/radiol.2016161509

    View details for PubMedID 28045603

    View details for PubMedCentralID PMC5410949

  • New Hypofractionation Radiation Strategies for Glioblastoma. Current oncology reports Azoulay, M., Shah, J., Pollom, E., Soltys, S. G. 2017; 19 (9): 58


    Glioblastoma (GBM) is the most common and lethal primary brain tumor in adults, with a median survival of less than 2 years despite the standard of care treatment of 6 weeks of chemoradiotherapy. We review the data investigating hypofractionated radiotherapy (HFRT) in the treatment of newly diagnosed GBM.Investigators have explored alternative radiotherapy strategies that shorten treatment duration with the goal of similar or improved survival while minimizing toxicity. HFRT over 1-3 weeks is already a standard of care for patients with advanced age or poor performance status. For young patients with good performance status, HFRT holds the promise of radiobiologically escalating the dose and potentially improving local control while maintaining quality of life. Through the use of shorter radiotherapy fractionation regimens coupled with novel systemic agents, improved outcomes for patients with GBM may be achieved.

    View details for DOI 10.1007/s11912-017-0616-3

    View details for PubMedID 28735440

  • Sinoatrial node toxicity after stereotactic ablative radiation therapy to lung tumors. Practical radiation oncology Qian, Y., Zhu, H., Pollom, E. L., Durkee, B. Y., Chaudhuri, A. A., Gensheimer, M. F., Diehn, M., Shultz, D. B., Loo, B. W. 2017


    Stereotactic ablative radiation therapy (SABR) is an established treatment for selected lung tumors. Sinoatrial node (SAN) toxicity after thoracic SABR has not been reported in the literature. We sought to understand the risk of SAN toxicity owing to incidental dose to the SAN from SABR.We conducted a retrospective review of patients with early-stage lung cancer or limited pulmonary metastases who underwent thoracic SABR to a right-sided central lung tumor (within 2 cm of the mainstem bronchus or other mediastinal structures) between January 2008 and December 2014, analyzed a subset whose treatment imparted dose to the SAN exceeding 10% of the prescription dose, and examined patient and treatment dosimetric characteristics. Mean follow-up interval was 28 months. Time to toxicity was defined from start of SABR.Of 47 patients with central tumors in the right lung treated with SABR reviewed, 13 met our study criteria. A contouring atlas of regional cardiac anatomy was created. One patient treated with SABR for non-small cell lung cancer at the right hilum developed symptomatic sick sinus syndrome, requiring pacemaker placement 6 months after treatment. Her acute presentation and short interval between SABR and onset of symptoms suggest that SAN toxicity was likely due to radiation-induced injury. Both her age and mean dose to her SAN were the third highest in our cohort. She remained free from cancer progression at 24 months' follow-up. Twelve additional patients who received significant dose to the SAN from SABR did not develop toxicity.While uncommon, SAN toxicity from SABR to right-sided central thoracic tumors should be recognized and followed in future studies.

    View details for DOI 10.1016/j.prro.2017.04.005

    View details for PubMedID 28669706

  • Cost-Effectiveness of Radiation and Chemotherapy for High-Risk Low-Grade Glioma. Neuro-oncology Qian, Y., Maruyama, S., Kim, H., Pollom, E. L., Kumar, K. A., Chin, A. L., Harris, J. P., Chang, D. T., Pitt, A., Bendavid, E., Owens, D. K., Durkee, B. Y., Soltys, S. G. 2017


    The addition of PCV (procarbazine, lomustine, vincristine) chemotherapy to radiotherapy (RT) for patients with high-risk (≥ 40 years old or sub-totally resected) low-grade glioma (LGG) results in an absolute median survival benefit of over 5 years. We evaluated the cost-effectiveness of this treatment strategy.A decision tree with an integrated three-state Markov model was created to follow patients with high risk LGG after surgery treated with RT vs. RT+PCV. Patients existed in one of 3 health states: stable, progressive, and dead. Survival and freedom from progression were modeled to reflect the results of RTOG 9802 using time-dependent transition probabilities. Health utility values and costs of care were derived from the literature and national registry databases. Analysis was conducted from the healthcare perspective. Deterministic and probabilistic sensitivity analysis explored uncertainty in model parameters.Modeled outcomes demonstrated agreement with clinical data in expected benefit of addition of PCV to RT. The addition of PCV to RT yielded an incremental benefit of 4.77 quality-adjusted life-years (QALYs) (9.94 for RT+PCV vs. 5.17 for RT alone) at an incremental cost of $48,635 ($188,234 for RT+PCV vs. $139,598 for RT alone), resulting in an incremental cost-effectiveness ratio of $10,186 per QALY gained. Probabilistic sensitivity analysis demonstrates that within modeled distributions of parameters, RT+PCV has 99.96% probability of being cost-effectiveness at a willingness-to-pay threshold of $100,000 per QALY.The addition of PCV to RT is a cost-effective treatment strategy for patients with high-risk LGG.

    View details for DOI 10.1093/neuonc/nox121

    View details for PubMedID 28666368

  • Impact of Intensity-Modulated Radiotherapy on Health Care Costs of Patients With Anal Squamous Cell Carcinoma. Journal of oncology practice Chin, A. L., Pollom, E. L., Qian, Y., Koong, A. C., Chang, D. T. 2017: JOP2017024810


    Drivers of variation in the cost of care after chemoradiotherapy for the management of anal squamous cell carcinoma (SCC) have not been fully elucidated. We sought to characterize the direct and indirect impact of radiotherapy modality on health care costs among patients with anal SCC.A retrospective cohort study was performed using the 2014 linkage of the SEER-Medicare database. We identified 1,025 patients with anal SCC diagnosed between 2001 and 2011 and treated with chemoradiotherapy. Propensity score matching was used to balance baseline differences between patients treated with intensity-modulated radiotherapy (IMRT) and those treated with three-dimensional conformal radiotherapy (3D-CRT). Differences in total, cancer-attributable, and procedure-specific costs between groups were measured.Radiation-related, patient out-of-pocket, and total costs in the 1-year period after radiotherapy start were all higher for the IMRT group than the 3D-CRT group (median total cost, $35,890 v $27,262, respectively; P < .001). Patients who received IMRT had lower cumulative costs associated with urgent hospitalizations and emergency department visits at both 9 months and 1 year after treatment start compared with a matched cohort of patients who received 3D-CRT (median, $711 v $4,957 at 1 year, respectively; P = .021).Although total costs of care were higher for IMRT compared with 3D-CRT, primarily as a result of higher radiotherapy-specific costs, IMRT was associated with decreased unplanned health care utilization costs starting at 9 months after treatment start. Radiotherapy-centered episodes of care may need to encompass a longer time horizon to capture the full cost savings associated with more advanced radiation modalities.

    View details for DOI 10.1200/JOP.2017.024810

    View details for PubMedID 29035618

  • Does radiotherapy still have a role in unresected biliary tract cancer? Cancer medicine Pollom, E. L., Alagappan, M., Park, L. S., Whittemore, A. S., Koong, A. C., Chang, D. T. 2017; 6 (1): 129-141


    The benefits of radiotherapy for inoperable biliary tract cancer remain unclear due to the lack of randomized data. We evaluated the impact of radiotherapy on survival in elderly patients using the SEER-Medicare database. Patients in the SEER-Medicare database with inoperable biliary tract tumors diagnosed between 1998 and 2011 were included. We used multivariate logistic regression to evaluate factors associated with treatment selection, and multivariate Cox regression and propensity score matching to evaluate treatment selection in relation to subsequent survival. Of the 2343 patients included, 451 (19%) received radiotherapy within 4 months of diagnosis. The use of radiotherapy declined over time, and was influenced by receipt of chemotherapy and patient age, race, marital status, poverty status, and tumor stage and type. Median survival was 9.3 (95% CI 8.7-9.7) months among patients who did not receive radiation and 10.0 (95% CI 9.1-11.3) months among those who received radiation, conditional on having survived 4 months. In patients who received chemotherapy (n = 1053), receipt of radiation was associated with improved survival, with an adjusted hazard ratio of 0.82 (95% 0.70-0.97, P = 0.02). In patients who did not receive chemotherapy (n = 1290), receipt of radiation was not associated with improved survival, with an adjusted hazard ratio of 1.09 (95% 0.91-1.30, P = 0.34). Propensity-scored matched analyses showed similar results. Despite the survival benefit associated with the addition of radiotherapy to chemotherapy, the use of radiation for unresectable biliary tract cancers has declined over time.

    View details for DOI 10.1002/cam4.975

    View details for PubMedID 27891822

  • Hypofractionated Intensity-Modulated Radiotherapy for Patients With Non-Small-Cell Lung Cancer. Clinical lung cancer Pollom, E. L., Qian, Y., Durkee, B. Y., von Eyben, R., Maxim, P. G., Shultz, D. B., Gensheimer, M., Diehn, M., Loo, B. W. 2016; 17 (6): 588-594


    Alternative treatment regimens are needed for patients with non-small cell lung cancer (NSCLC) who cannot receive definitive treatment with concurrent chemoradiotherapy, surgery, or stereotactic ablative radiotherapy (SABR).We report survival, patterns of failure and toxicity outcomes for patients with NSCLC who were not eligible for surgical resection, concurrent chemoradiotherapy, or SABR and underwent hypofractionated intensity-modulated radiotherapy (IMRT). Kaplan-Meier survival analysis was used to evaluate the progression-free and overall survival. Competing risk analysis was used to evaluate in-field, locoregional, and distant failure.A total of 42 patients treated to 52.5 to 60 Gy in 15 fractions were included. Most of the patients had metastatic or recurrent disease (64%) and a relatively large, centrally located tumor burden (74%). The median follow-up period was 13 months (interquartile range, 6-18 months). All patients received the total prescribed dose. The median survival was 15.1 months. The overall and progression-free survival rates at 1 year were 63% and 22.5%, respectively. The pattern of failure was predominantly distant, with only 2% of patients experiencing isolated in-field recurrence. The cumulative incidence of in-field failure at 6 and 12 months was 2.5% (95% confidence interval, 0.4%-15.6%) and 16.1% (95% confidence interval, 7.5%-34.7%), respectively. The risk of esophageal toxicity was associated with the esophageal mean dose, maximal point dose, and dose to the 5 cm(3) volume. The risk of pneumonitis was associated with the lung mean dose and volume receiving 18 Gy.Hypofractionated IMRT without concurrent chemotherapy provides favorable rates of local control and survival for well-selected patients with NSCLC who cannot tolerate standard definitive therapy.

    View details for DOI 10.1016/j.cllc.2016.05.024

    View details for PubMedID 27378172

  • Prognostic value of midtreatment FDG-PET in oropharyngeal cancer. Head & neck Pollom, E. L., Song, J., Durkee, B. Y., Aggarwal, S., Bui, T., von Eyben, R., Li, R., Brizel, D. M., Loo, B. W., Le, Q., Hara, W. Y. 2016; 38 (10): 1472-1478


    Prognostic metabolic imaging indices are needed for risk stratification for patients with locally advanced oropharyngeal cancer.We retrospectively examined pretreatment and midtreatment fluorodeoxyglucose-positron emission tomography (FDG-PET) parameters in patients with locally advanced oropharyngeal cancer who were treated with definitive chemoradiation.A total of 74 patients were evaluated. Pretreatment metabolic tumor volume (MTV) using threshold of 50% standardized uptake value (SUV) maximum (MTV50% ) was associated with progression-free survival (PFS; p = .003; hazard ratio [HR] = 1.57 per 10 cc; 95% confidence interval [CI] = 1.17-2.11) and overall survival (OS; p = .01; HR = 1.36 per 10 cc; 95% CI = 1.07-1.74). Midtreatment MTV using a threshold of SUV 2.0 (MTV2.0 ) was associated with PFS (p < .001; HR = 1.24 per 10 cc; 95% CI = 1.10-1.39) and OS (p = .009; HR = 1.21 per 10 cc; 95% CI = 1.05-1.39). Nodal total lesion glycolysis (TLG) velocity >5% decrease/week was associated with improved PFS (p = .04; HR = 0.37; 95% CI = 0.15-0.95).Metabolic response during chemoradiation is associated with survival in locally advanced oropharyngeal cancer and may aid with risk-adapting treatment. © 2016 Wiley Periodicals, Inc. Head Neck, 2016.

    View details for DOI 10.1002/hed.24454

    View details for PubMedID 27043927

  • Nomogram to Predict Risk of Lymph Node Metastases in Patients With Endometrioid Endometrial Cancer. International journal of gynecological pathology Pollom, E. L., Conklin, C. M., von Eyben, R., Folkins, A. K., Kidd, E. A. 2016; 35 (5): 395-401


    Pelvic lymphadenectomy in early-stage endometrial cancer is controversial, but the findings influence prognosis and treatment decisions. Noninvasive tools to identify women at high risk of lymph node metastasis can assist in determining the need for lymph node dissection and adjuvant treatment for patients who do not have a lymph node dissection performed initially. A retrospective review of surgical pathology was conducted for endometrioid endometrial adenocarcinoma at our institution. Univariate and multivariate logistic regression analysis of selected pathologic features were performed. A nomogram to predict for lymph node metastasis was constructed. From August 1996 to October 2013, 296 patients underwent total abdominal or laparoscopic hysterectomy, bilateral salpingo-oophorectomy, and selective lymphadenectomy for endometrioid endometrial adenocarcinoma. Median age at surgery was 62.7 yr (range, 24.9-93.6 yr). Median number of lymph nodes removed was 13 (range, 1-72). Of all patients, 38 (12.8%) had lymph node metastases. On univariate analysis, tumor size ≥4 cm, grade, lymphovascular space involvement, cervical stromal involvement, adnexal or serosal or parametrial involvement, positive pelvic washings, and deep (more than one half) myometrial invasion were all significantly associated with lymph node involvement. In a multivariate model, lymphovascular space involvement, deep myometrial invasion, and cervical stromal involvement remained significant predictors of nodal involvement, whereas tumor size of ≥4 cm was borderline significant. A lymph node predictive nomogram was constructed using these factors. Our nomogram can help estimate risk of nodal disease and aid in directing the need for additional surgery or adjuvant therapy in patients without lymph node surgery. Lymphovascular space involvement is the most important predictor for lymph node metastases, regardless of grade, and should be consistently assessed.

    View details for DOI 10.1097/PGP.0000000000000246

    View details for PubMedID 26598977

  • Quantitative Analysis of (18)F-Fluorodeoxyglucose Positron Emission Tomography Identifies Novel Prognostic Imaging Biomarkers in Locally Advanced Pancreatic Cancer Patients Treated With Stereotactic Body Radiation Therapy. International journal of radiation oncology, biology, physics Cui, Y., Song, J., Pollom, E., Alagappan, M., Shirato, H., Chang, D. T., Koong, A. C., Li, R. 2016; 96 (1): 102-109


    To identify prognostic biomarkers in pancreatic cancer using high-throughput quantitative image analysis.In this institutional review board-approved study, we retrospectively analyzed images and outcomes for 139 locally advanced pancreatic cancer patients treated with stereotactic body radiation therapy (SBRT). The overall population was split into a training cohort (n=90) and a validation cohort (n=49) according to the time of treatment. We extracted quantitative imaging characteristics from pre-SBRT (18)F-fluorodeoxyglucose positron emission tomography, including statistical, morphologic, and texture features. A Cox proportional hazard regression model was built to predict overall survival (OS) in the training cohort using 162 robust image features. To avoid over-fitting, we applied the elastic net to obtain a sparse set of image features, whose linear combination constitutes a prognostic imaging signature. Univariate and multivariate Cox regression analyses were used to evaluate the association with OS, and concordance index (CI) was used to evaluate the survival prediction accuracy.The prognostic imaging signature included 7 features characterizing different tumor phenotypes, including shape, intensity, and texture. On the validation cohort, univariate analysis showed that this prognostic signature was significantly associated with OS (P=.002, hazard ratio 2.74), which improved upon conventional imaging predictors including tumor volume, maximum standardized uptake value, and total legion glycolysis (P=.018-.028, hazard ratio 1.51-1.57). On multivariate analysis, the proposed signature was the only significant prognostic index (P=.037, hazard ratio 3.72) when adjusted for conventional imaging and clinical factors (P=.123-.870, hazard ratio 0.53-1.30). In terms of CI, the proposed signature scored 0.66 and was significantly better than competing prognostic indices (CI 0.48-0.64, Wilcoxon rank sum test P<1e-6).Quantitative analysis identified novel (18)F-fluorodeoxyglucose positron emission tomography image features that showed improved prognostic value over conventional imaging metrics. If validated in large, prospective cohorts, the new prognostic signature might be used to identify patients for individualized risk-adaptive therapy.

    View details for DOI 10.1016/j.ijrobp.2016.04.034

    View details for PubMedID 27511850

  • Cost-Effectiveness of Pertuzumab in Human Epidermal Growth Factor Receptor 2-Positive Metastatic Breast Cancer. Journal of clinical oncology Durkee, B. Y., Qian, Y., Pollom, E. L., King, M. T., Dudley, S. A., Shaffer, J. L., Chang, D. T., Gibbs, I. C., Goldhaber-Fiebert, J. D., Horst, K. C. 2016; 34 (9): 902-909


    The Clinical Evaluation of Pertuzumab and Trastuzumab (CLEOPATRA) study showed a 15.7-month survival benefit with the addition of pertuzumab to docetaxel and trastuzumab (THP) as first-line treatment for patients with human epidermal growth factor receptor 2 (HER2) -overexpressing metastatic breast cancer. We performed a cost-effectiveness analysis to assess the value of adding pertuzumab.We developed a decision-analytic Markov model to evaluate the cost effectiveness of docetaxel plus trastuzumab (TH) with or without pertuzumab in US patients with metastatic breast cancer. The model followed patients weekly over their remaining lifetimes. Health states included stable disease, progressing disease, hospice, and death. Transition probabilities were based on the CLEOPATRA study. Costs reflected the 2014 Medicare rates. Health state utilities were the same as those used in other recent cost-effectiveness studies of trastuzumab and pertuzumab. Outcomes included health benefits expressed as discounted quality-adjusted life-years (QALYs), costs in US dollars, and cost effectiveness expressed as an incremental cost-effectiveness ratio. One- and multiway deterministic and probabilistic sensitivity analyses explored the effects of specific assumptions.Modeled median survival was 39.4 months for TH and 56.9 months for THP. The addition of pertuzumab resulted in an additional 1.82 life-years gained, or 0.64 QALYs, at a cost of $713,219 per QALY gained. Deterministic sensitivity analysis showed that THP is unlikely to be cost effective even under the most favorable assumptions, and probabilistic sensitivity analysis predicted 0% chance of cost effectiveness at a willingness to pay of $100,000 per QALY gained.THP in patients with metastatic HER2-positive breast cancer is unlikely to be cost effective in the United States.

    View details for DOI 10.1200/JCO.2015.62.9105

    View details for PubMedID 26351332

  • Albumin and Neutrophil-Lymphocyte Ratio (NLR) Predict Survival in Patients With Pancreatic Adenocarcinoma Treated With SBRT. American journal of clinical oncology Alagappan, M., Pollom, E. L., von Eyben, R., Kozak, M. M., Aggarwal, S., Poultsides, G. A., Koong, A. C., Chang, D. T. 2016: -?


    To determine if pretreatment nutritional status and inflammatory markers correlate with survival in patients with locally advanced pancreatic adenocarcinoma treated with stereotactic body radiotherapy (SBRT).We retrospectively reviewed 208 patients with newly diagnosed, locally advanced pancreatic adenocarcinoma treated with SBRT at our institution from 2002 to 2014. Laboratory values were collected before SBRT, including hemoglobin, platelets, albumin, red blood cell, white blood cell, neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio, and tumor markers CA 19-9 and CEA. Patients were followed every 3 months with computed tomography (CT) and/or positron emission tomography-CT imaging to monitor for local recurrence and overall survival (OS).Median follow-up after SBRT was 7.5 months (interquartile range, 4.6 to 12.0 mo) for all patients. Median OS for patients with NLR>5 compared with NLR≤5 was 6.9 and 8.5 months, respectively (P=0.0057). On univariate analysis, receipt of chemotherapy (P=0.05, hazard ratio [HR]=0.69), increased albumin (P=0.002, HR=0.64), increased red blood cell (P=0.05, HR=0.75), increased lymphocyte count (P=0.002, HR=0.66), decreased CEA (P=0.01, HR=0.96), and NLR≤5 (P=0.01, HR=0.65) correlated with improved OS. On multivariate analysis, higher albumin (P=0.03, HR=0.70), receipt of chemotherapy (P=0.007, HR=0.56), and NLR≤5 (P=0.02, HR=0.66) correlated with better survival.Preradiotherapy low albumin levels and NLR>5 correlate with decreased survival in patients with locally advanced pancreatic adenocarcinoma treated with SBRT, indicating the prognostic value of systemic inflammatory markers (such as NLR) and a role of nutritional supplementation to improve outcomes in these patients. Further investigation is warranted.

    View details for PubMedID 26757436

  • A prospective study of electronic quality of life assessment using tablet devices during and after treatment of head and neck cancers. Oral oncology Pollom, E. L., Wang, E., Bui, T. T., Ognibene, G., von Eyben, R., Divi, V., Sunwoo, J., Kaplan, M., Dimitri Colevas, A., Le, Q., Hara, W. Y. 2015; 51 (12): 1132-1137


    Electronic data collection is increasingly used for quality of life (QOL) assessments in the field of oncology. It is important to assess the feasibility of these new data capture technologies.Patients at our institution who were 18years or older with a pathological diagnosis of head and neck cancer were prospectively enrolled. Each patient completed two questionnaires [EORTC-QLQ-C30 and EORTC-QLQ-H&N35] administered on a touch-screen tablet device (iPad™) at initial consult, during treatment, at the completion of treatment and at each subsequent follow up visit for one year after treatment.A total of 50 patients were included in this study. Although all patients completed the surveys at the initial consult, 86% of initially enrolled patients completed surveys at the end of radiation treatment, and 48% of initially enrolled patients completed surveys by the fourth follow-up visit. Average time to complete the survey for all patients over all time points was 9.8min (standard deviation 6.1). Age as a continuous variable was significantly associated with time for survey completion (p<0.001), with older age associated with longer survey completion times.QOL assessment using tablet devices in head and neck cancer patients is feasible, but may be more challenging in elderly patients. Patients ⩾70years old may benefit from more assistance with electronic forms and should be allotted more time for completing tablet-based QOL surveys.

    View details for DOI 10.1016/j.oraloncology.2015.10.003

    View details for PubMedID 26475062

  • Concurrent Vismodegib and Radiotherapy for Recurrent, Advanced Basal Cell Carcinoma. JAMA dermatology Pollom, E. L., Bui, T. T., Chang, A. L., Colevas, A. D., Hara, W. Y. 2015; 151 (9): 998-1001


    Vismodegib is a targeted agent recently approved for treating patients who develop recurrent or locally advanced basal cell carcinoma (BCC), and will inevitably be integrated into existing therapy for advanced BCC as it becomes increasingly used. Improved understanding of how vismodegib interacts with other treatment modalities, including radiotherapy, would help optimize multidisciplinary therapy and clinical outcomes.We report 2 cases of recurrent, advanced BCC treated from April 1, 2012, through October 31, 2014, with concurrent radiotherapy and vismodegib. Concurrent treatment appeared to be well tolerated and efficacious, with both patients having no evidence of progressive disease at last follow-up.We found that the combination of vismodegib and radiotherapy is feasible for patients with recurrent or locally advanced BCC and that combined use of currently available therapies for advanced BCC warrants further prospective study.

    View details for DOI 10.1001/jamadermatol.2015.0326

    View details for PubMedID 25874733

  • Treatment Approaches to Locally Advanced Pancreatic Adenocarcinoma. Hematology/oncology clinics of North America Pollom, E. L., Koong, A. C., Ko, A. H. 2015; 29 (4): 741-759


    This article focuses on the management of locally advanced pancreatic cancer, which should be treated as a distinct entity separate from metastatic disease and borderline resectable disease. Although the role, timing, and sequencing of radiation relative to systemic therapy in this disease are controversial, an emerging treatment paradigm involves induction chemotherapy, followed by consolidative chemoradiation in patients who do not progress. In addition, new chemotherapy regimens as well as novel radiosensitizers have shown promise and need to be tested further in the locally advanced setting. Advances in radiotherapy have enabled stereotactic body radiotherapy and should continue to be prospectively evaluated.

    View details for DOI 10.1016/j.hoc.2015.04.005

    View details for PubMedID 26226908

  • Gastrointestinal Toxicities With Combined Antiangiogenic and Stereotactic Body Radiation Therapy INTERNATIONAL JOURNAL OF RADIATION ONCOLOGY BIOLOGY PHYSICS Pollom, E. L., Deng, L., Pai, R. K., Brown, J. M., Giaccia, A., Loo, B. W., Shultz, D. B., Quynh Thu Le, Q. T., Koong, A. C., Chang, D. T. 2015; 92 (3): 568-576
  • TU-CD-BRB-08: Radiomic Analysis of FDG-PET Identifies Novel Prognostic Imaging Biomarkers in Locally Advanced Pancreatic Cancer Patients Treated with SBRT. Medical physics Cui, Y., Song, J., Pollom, E., Shirato, H., Chang, D., Koong, A., Li, R. 2015; 42 (6): 3604-?


    This study aims to identify novel prognostic imaging biomarkers in locally advanced pancreatic cancer (LAPC) using quantitative, high-throughput image analysis.86 patients with LAPC receiving chemotherapy followed by SBRT were retrospectively studied. All patients had a baseline FDG-PET scan prior to SBRT. For each patient, we extracted 435 PET imaging features of five types: statistical, morphological, textural, histogram, and wavelet. These features went through redundancy checks, robustness analysis, as well as a prescreening process based on their concordance indices with respect to the relevant outcomes. We then performed principle component analysis on the remaining features (number ranged from 10 to 16), and fitted a Cox proportional hazard regression model using the first 3 principle components. Kaplan-Meier analysis was used to assess the ability to distinguish high versus low-risk patients separated by median predicted survival. To avoid overfitting, all evaluations were based on leave-one-out cross validation (LOOCV), in which each holdout patient was assigned to a risk group according to the model obtained from a separate training set.For predicting overall survival (OS), the most dominant imaging features were wavelet coefficients. There was a statistically significant difference in OS between patients with predicted high and low-risk based on LOOCV (hazard ratio: 2.26, p<0.001). Similar imaging features were also strongly associated with local progression-free survival (LPFS) (hazard ratio: 1.53, p=0.026) on LOOCV. In comparison, neither SUVmax nor TLG was associated with LPFS (p=0.103, p=0.433) (Table 1). Results for progression-free survival and distant progression-free survival showed similar trends.Radiomic analysis identified novel imaging features that showed improved prognostic value over conventional methods. These features characterize the degree of intra-tumor heterogeneity reflected on FDG-PET images, and their biological underpinnings warrant further investigation. If validated in large, prospective cohorts, this method could be used to stratify patients based on individualized risk.

    View details for DOI 10.1118/1.4925593

    View details for PubMedID 26128895

  • TU-AB-BRA-10: Prognostic Value of Intra-Radiation Treatment FDG-PET and CT Imaging Features in Locally Advanced Head and Neck Cancer. Medical physics Song, J., Cui, Y., Pollom, E., Durkee, B., Aggarwal, S., Bui, T., Le, Q., Loo, B., Hara, W., Li, R. 2015; 42 (6): 3588-?


    To predict response to radiation treatment using computational FDG-PET and CT images in locally advanced head and neck cancer (HNC).68 patients with State III-IVB HNC treated with chemoradiation were included in this retrospective study. For each patient, we analyzed primary tumor and lymph nodes on PET and CT scans acquired both prior to and during radiation treatment, which led to 8 combinations of image datasets. From each image set, we extracted high-throughput, radiomic features of the following types: statistical, morphological, textural, histogram, and wavelet, resulting in a total of 437 features. We then performed unsupervised redundancy removal and stability test on these features. To avoid over-fitting, we trained a logistic regression model with simultaneous feature selection based on least absolute shrinkage and selection operator (LASSO). To objectively evaluate the prediction ability, we performed 5-fold cross validation (CV) with 50 random repeats of stratified bootstrapping. Feature selection and model training was solely conducted on the training set and independently validated on the holdout test set. Receiver operating characteristic (ROC) curve of the pooled Result and the area under the ROC curve (AUC) was calculated as figure of merit.For predicting local-regional recurrence, our model built on pre-treatment PET of lymph nodes achieved the best performance (AUC=0.762) on 5-fold CV, which compared favorably with node volume and SUVmax (AUC=0.704 and 0.449, p<0.001). Wavelet coefficients turned out to be the most predictive features. Prediction of distant recurrence showed a similar trend, in which pre-treatment PET features of lymph nodes had the highest AUC of 0.705.The radiomics approach identified novel imaging features that are predictive to radiation treatment response. If prospectively validated in larger cohorts, they could aid in risk-adaptive treatment of HNC.

    View details for DOI 10.1118/1.4925515

    View details for PubMedID 26128812

  • Value of Surveillance Studies for Patients With Stage I to II Diffuse Large B-Cell Lymphoma in the Rituximab Era. International journal of radiation oncology, biology, physics Hiniker, S. M., Pollom, E. L., Khodadoust, M. S., Kozak, M. M., Xu, G., Quon, A., Advani, R. H., Hoppe, R. T. 2015; 92 (1): 99-106


    The role of surveillance studies in limited-stage diffuse large B-cell lymphoma (DLBCL) in the rituximab era has not been well defined. We sought to evaluate the use of imaging (computed tomography [CT] and positron emission tomography [PET]-CT) scans and lactate dehydrogenase (LDH) in surveillance of patients with stage I to II DLBCL.A retrospective analysis was performed of patients who received definitive treatment between 2000 and 2013.One hundred sixty-two consecutive patients with stage I to II DLBCL were treated with chemotherapy +/- rituximab, radiation, or combined modality therapy. The 5-year rates of overall survival (OS) and freedom from progression (FFP) were 81.2% and 80.8%, respectively. Of the 162 patients, 124 (77%) were followed up with at least 1 surveillance PET scan beyond end-of-treatment scans; of those, 94 of 124 (76%) achieved a complete metabolic response on PET scan after completion of chemotherapy, and this was associated with superior FFP (P=.01, HR=0.3) and OS (P=.01, HR 0.3). Eighteen patients experienced relapse after initial response to therapy. Nine relapses were initially suspected by surveillance imaging studies (8 PET, 1 CT), and 9 were suspected clinically (5 by patient-reported symptoms and 4 by symptoms and physical examination). No relapses were detected by surveillance LDH. The median duration from initiation of treatment to relapse was 14.3 months among patients with relapses suspected by imaging, and 59.8 months among patients with relapses suspected clinically (P=.077). There was no significant difference in OS from date of first therapy or OS after relapse between patients whose relapse was suspected by imaging versus clinically. Thirteen of 18 patients underwent successful salvage therapy after relapse.A complete response on PET scan immediately after initial chemotherapy is associated with superior FFP and OS in stage I to II DLBCL. The use of PET scans as posttreatment surveillance is not associated with a survival advantage. LDH is not a sensitive marker for relapse. Our results argue for limiting the use of posttreatment surveillance in patients with limited-stage DLBCL.

    View details for DOI 10.1016/j.ijrobp.2015.01.039

    View details for PubMedID 25863757

  • Outcomes After Stereotactic Body Radiotherapy or Radiofrequency Ablation for Hepatocellular Carcinoma. Journal of clinical oncology : official journal of the American Society of Clinical Oncology Wahl, D. R., Stenmark, M. H., Tao, Y., Pollom, E. L., Caoili, E. M., Lawrence, T. S., Schipper, M. J., Feng, M. 2015


    Data guiding selection of nonsurgical treatment of hepatocellular carcinoma (HCC) are lacking. We therefore compared outcomes between stereotactic body radiotherapy (SBRT) and radiofrequency ablation (RFA) for HCC.From 2004 to 2012, 224 patients with inoperable, nonmetastatic HCC underwent RFA (n = 161) to 249 tumors or image-guided SBRT (n = 63) to 83 tumors. We applied inverse probability of treatment weighting to adjust for imbalances in treatment assignment. Freedom from local progression (FFLP) and toxicity were retrospectively analyzed.RFA and SBRT groups were similar with respect to number of lesions treated per patient, type of underlying liver disease, and tumor size (median, 1.8 v 2.2 cm in maximum diameter; P = .14). However, the SBRT group had lower pretreatment Child-Pugh scores (P = .003), higher pretreatment alpha-fetoprotein levels (P = .04), and a greater number of prior liver-directed treatments (P < .001). One- and 2-year FFLP for tumors treated with RFA were 83.6% and 80.2% v 97.4% and 83.8% for SBRT. Increasing tumor size predicted for FFLP in patients treated with RFA (hazard ratio [HR], 1.54 per cm; P = .006), but not with SBRT (HR, 1.21 per cm; P = .617). For tumors ≥ 2 cm, there was decreased FFLP for RFA compared with SBRT (HR, 3.35; P = .025). Acute grade 3+ complications occurred after 11% and 5% of RFA and SBRT treatments, respectively (P = .31). Overall survival 1 and 2 years after treatment was 70% and 53% after RFA and 74% and 46% after SBRT.Both RFA and SBRT are effective local treatment options for inoperable HCC. Although these data are retrospective, SBRT appears to be a reasonable first-line treatment of inoperable, larger HCC.

    View details for DOI 10.1200/JCO.2015.61.4925

    View details for PubMedID 26628466

  • Single-versus Multifraction Stereotactic Body Radiation Therapy for Pancreatic Adenocarcinoma: Outcomes and Toxicity INTERNATIONAL JOURNAL OF RADIATION ONCOLOGY BIOLOGY PHYSICS Pollom, E. L., Alagappan, M., von Eyben, R., Kunz, P. L., Fisher, G. A., Ford, J. A., Poultsides, G. A., Visser, B. C., Norton, J. A., Kamaya, A., Cox, V. L., Columbo, L. A., Koong, A. C., Chang, D. T. 2014; 90 (4): 918-925
  • Stereotactic Body Radiation Therapy for Primary and Metastatic Liver Tumors TRANSLATIONAL ONCOLOGY Liu, E., Stenmark, M. H., Schipper, M. J., Balter, J. M., Kessler, M. L., Caoili, E. M., Lee, O. E., Ben-Josef, E., Lawrence, T. S., Feng, M. 2013; 6 (4): 442-446


    The full potential of stereotactic body radiation therapy (SBRT), in the treatment of unresectable intrahepatic malignancies, has yet to be realized as our experience is still limited. Thus, we evaluated SBRT outcomes for primary and metastatic liver tumors, with the goal of identifying factors that may aid in optimization of therapy.From 2005 to 2010, 62 patients with 106 primary and metastatic liver tumors were treated with SBRT to a median biologic effective dose (BED) of 100 Gy (42.6-180). The majority of patients received either three (47%) or five fractions (48%). Median gross tumor volume (GTV) was 8.8 cm(3) (0.2-222.4).With a median follow-up of 18 months (0.46-46.8), freedom from local progression (FFLP) was observed in 97 of 106 treated tumors, with 1- and 2-year FFLP rates of 93% and 82%. Median overall survival (OS) for all patients was 25.2 months, with 1- and 2-year OS of 81% and 52%. Neither BED nor GTV significantly predicted for FFLP. Local failure was associated with a higher risk of death [hazard ratio (HR) = 5.1, P = .0007]. One Child-Pugh Class B patient developed radiation-induced liver disease. There were no other significant toxicities.SBRT provides excellent local control for both primary and metastatic liver lesions with minimal toxicity. Future studies should focus on appropriate selection of patients and on careful assessment of liver function to maximize both the safety and efficacy of treatment.

    View details for DOI 10.1593/tlo.12448

    View details for Web of Science ID 000328361500007

    View details for PubMedID 23908687

  • Selective radiosensitization of p53 mutant pancreatic cancer cells by combined inhibition of Chk1 and PARP1 CELL CYCLE Vance, S. M., Liu, E., Zhao, L., Parsels, J. D., Parsels, L. A., Brown, J. L., Maybaum, J., Lawrence, T. S., Morgan, M. A. 2011; 10 (24): 4321-4329


    We have recently shown that inhibition of HRR (homologous recombination repair) by Chk1 (checkpoint kinase 1) inhibition radiosensitizes pancreatic cancer cells and others have demonstrated that Chk1 inhibition selectively sensitizes p53 mutant tumor cells. Furthermore, PARP1 [poly (ADP-ribose) polymerase-1] inhibitors dramatically radiosensitize cells with DNA double strand break repair defects. Thus, we hypothesized that inhibition of HRR (mediated by Chk1 via AZD7762) and PARP1 [via olaparib (AZD2281)] would selectively sensitize p53 mutant pancreatic cancer cells to radiation. We also used 2 isogenic p53 cell models to assess the role of p53 status in cancer cells and intestinal epithelial cells to assess overall cancer specificity. DNA damage response and repair were assessed by flow cytometry, γH2AX, and an HRR reporter assay. We found that the combination of AZD7762 and olaparib produced significant radiosensitization in p53 mutant pancreatic cancer cells and in all of the isogenic cancer cell lines. The magnitude of radiosensitization by AZD7762 and olaparib was greater in p53 mutant cells compared with p53 wild type cells. Importantly, normal intestinal epithelial cells were not radiosensitized. The combination of AZD7762 and olaparib caused G 2 checkpoint abrogation, inhibition of HRR, and persistent DNA damage responses. These findings demonstrate that the combination of Chk1 and PARP1 inhibition selectively radiosensitizes p53 mutant pancreatic cancer cells. Furthermore, these studies suggest that inhibition of HRR by Chk1 inhibitors may be a useful strategy for selectively inducing a BRCA1/2 'deficient-like' phenotype in p53 mutant tumor cells, while sparing normal tissue.

    View details for DOI 10.4161/cc.10.24.18661

    View details for Web of Science ID 000298407200033

    View details for PubMedID 22134241

  • Resident Workload, Pager Communications, and Quality of Care 5th Annual Academic Surgical Congress Patel, S. P., Lee, J. S., Ranney, D. N., Al-Holou, S. N., Frost, C. M., Harris, M. E., Lewin, S. A., Liu, E., Madenci, A., Majkrzak, A. A., Nelson, J., Peterson, S. F., Serecky, K. A., Wilkinson, D. A., Wojcik, B. M., Englesbe, M. J., Lynch, R. J. SPRINGER. 2010: 2524–29


    With the recent regulations limiting resident work hours, it has become more important to understand how residents spend their time. The volume and content of the pages they receive provide a valuable source of information that give insight into their workload and help identify inefficiencies in hospital communication. We hypothesized that above a certain workload threshold, paging data would suggest breakdowns in communication and implications for quality of care. All pages sent to six general surgery interns at the University of Michigan over the course of one academic year (7/1/2008-6/30/2009) were retrospectively categorized by sender type, message type, message modifier, and message quality. Census, discharge, and admission information for each intern service were also collected, and intern duties were further analyzed with respect to schedule. "On-call" days were defined as days on which the intern bore responsibility for care of all admitted floor patients. The interns received a total of 9,843 pages during the study period. During on-call shifts, each intern was paged an average of 57 ± 3 times, and those on non-call shifts received an average of 12 ± 3 pages. Floor/intensive care unit (ICU) nurses represented 32% of the page volume received by interns. Interestingly, as patient volume increased, there was a decrease in the number of pages received per patient. By contrast, at higher patient volumes, there was a trend toward an increasing percentage of urgent pages per patient. At high intern workloads, our data suggest no major communication breakdowns but reveal the potential for inferior quality of care.

    View details for DOI 10.1007/s00268-010-0740-9

    View details for Web of Science ID 000282506500004

    View details for PubMedID 20703470

  • Connectivity Need Not Come at the Expense of Professionalism ACADEMIC MEDICINE Parikh, S. M., Liu, E., White, C. B. 2010; 85 (6): 930-930

    View details for DOI 10.1097/ACM.0b013e3181dbe54b

    View details for Web of Science ID 000279377300004

    View details for PubMedID 20505384