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  • Protracted venous infusion 5-fluorouracil with concomitant radiotherapy compared with bolus 5-fluorouracil for unresectable pancreatic cancer AMERICAN JOURNAL OF CLINICAL ONCOLOGY-CANCER CLINICAL TRIALS Mehta, V. K., Poen, J. C., Ford, J. M., Oberhelman, H. A., Vierra, M. A., Bastidas, A. J., Fisher, G. A. 2001; 24 (2): 155-159

    Abstract

    Radiation therapy (RT) with concurrent 5-fluorouracil (5-FU) administered by protracted venous infusion (PVI) replaced our prior institutional protocol of RT with bolus administration of 5-FU as standard therapy for unresectable pancreatic cancer in 1994. In this article, we compare the treatment intensity, toxicity, and outcome for patients with unresectable pancreatic cancer treated on these sequential protocols. Fifty-four patients, 27 on each protocol, with biopsy-confirmed pancreatic cancer received chemoradiotherapy. The radiotherapy field included the gross tumor volume and regional lymph nodes to a dose of 45 Gy, followed by "boost" to the gross tumor volume to 54 Gy to 60 Gy. From 1987 to 1994, patients received concurrent 5-FU administered by bolus injection, at a dose of 500 mg/m2 on days 1 to 3 and days 29 to 31 of RT. After December 1994, 5-FU was administered by PVI (200-250 mg/m2) beginning on day 1 and continuing until the completion of RT. The chemotherapy treatment intensity was increased in the group receiving 5-FU by PVI, as evidenced by an increased average weekly and cumulative dose of 5-FU (p < 0.01). The radiotherapy treatment intensity was equivalent between the two groups. The incidence of objectively quantified toxicity was not statistically different between treatment groups. Overall survival remained poor in both treatment groups. With a median follow-up of 18 months (range: 3-30 months) for surviving patients, the 6-month, 1-year, and 2-year survivals for the PVI 5-FU-treated group versus the bolus 5-FU-treated group were 56% versus 52%, 34% versus 18%, and 22% versus 13%, respectively (p = 0.9). Radiotherapy with concomitant 5-FU by PVI results in a greater weekly and total dose of chemotherapy. The method of 5-FU administration (bolus versus PVI) did not change the RT treatment intensity, experienced toxicity, or overall survival.

    View details for Web of Science ID 000168186300012

    View details for PubMedID 11319291

  • Adjuvant chemoradiotherapy for "unfavorable" carcinoma of the ampulla of vater - Preliminary report ARCHIVES OF SURGERY Mehta, V. K., Fisher, G. A., Ford, J. M., Poen, J. C., Vierra, M. A., Oberhelman, H. A., Bastidas, A. J. 2001; 136 (1): 65-69

    Abstract

    Adjuvant chemoradiotherapy decreases the risk of local recurrence in patients with adenocarcinoma of the ampulla of Vater and high-risk features. Adjuvant chemoradiotherapy for this population can be administered safely and without much morbidity.Controlled, prospective, single-arm study.Tertiary care referral hospital.From June 1995 to March 1999, 12 patients (7 men and 5 women; median age, 66 years; age range, 38-78 years) with "unfavorable" ampullary carcinoma were treated with adjuvant chemoradiotherapy. All patients underwent pancreaticoduodenectomy, and all pathologic findings were confirmed at Stanford University Medical Center, Stanford, Calif. Unfavorable features were defined as involved lymph nodes (n = 10), involved surgical margins (n = 1), poorly differentiated histological features (n = 3), tumor size greater than 2 cm (n = 6), or the presence of neurovascular invasion (n = 4).Four to 6 weeks after undergoing pylorus-preserving pancreaticoduodenectomy with regional lymphadenectomy, patients began adjuvant chemoradiotherapy consisting of concurrent radiotherapy (45 Gy) and fluorouracil by protracted venous infusion (225-250 mg/m(2) per day, 7 days per week) for 5 weeks.Local recurrence, distant recurrence, overall survival rate, and treatment-related toxic effects.All patients completed the prescribed treatment course. Toxic effects were assessed twice a week during treatment and graded according to the National Cancer Institute Common Toxicity Criteria Scale. One patient required a treatment interruption of 1 week for grade III nausea/vomiting. No grade IV or V toxic effects were observed. At median follow-up of 24 months (range, 13-50 months), 8 of 12 patients were alive and disease free. One patient was alive but had disease recurrence. Three patients died of this disease (liver metastases). Actuarial overall survival at 2 years was 89%, and median survival was 34 months. One surviving patient developed a local recurrence and a lung lesion. Actuarial overall survival and median survival were better than in a parallel cohort with resected high-risk pancreatic cancer (n = 26) treated with the same adjuvant chemoradiotherapy regimen (median survival, 34 vs 14 months; P<.004).Adjuvant chemoradiotherapy for carcinoma of the ampulla of Vater is well tolerated and might improve control of this disease in patients with unfavorable features.

    View details for Web of Science ID 000166307500014

    View details for PubMedID 11146780

  • Adjuvant radiotherapy and concomitant 5-fluorouracil by protracted venous infusion for resected pancreatic cancer INTERNATIONAL JOURNAL OF RADIATION ONCOLOGY BIOLOGY PHYSICS Mehta, V. K., Fisher, G. A., Ford, J. M., Oberhelman, H. A., Vierra, M. A., Bastidas, A. J., Poen, J. C. 2000; 48 (5): 1483-1487

    Abstract

    To assess the toxicity and clinical benefit from adjuvant chemoradiotherapy consisting of protracted venous infusion 5-fluorouracil (5-FU) and concomitant radiotherapy in patients with resected pancreatic cancer.Between 1994 and 1999, 52 patients who underwent pancreaticoduodenectomy received adjuvant chemoradiotherapy. The tumor bed and regional nodes received a dose of 45 Gy in fractions of 1.8 Gy followed by boost to the tumor bed if the surgical margins were involved (total dose, 54 Gy). The patients also received concomitant 5-FU by protracted venous infusion (200-250 mg/m(2)/day, 7 days/week) during the entire radiotherapy course.Fifty-two patients (30 men, 22 women) were enrolled and treated on this protocol. The median age was 63 years (range, 38-78 years), and the median Karnofsky Performance Status was 80 (range, 70-100). Thirty-five percent had involved surgical margins and 59% had involved lymph nodes. All patients completed therapy, and there were no Grade IV/V toxicities observed. With median follow-up of 24 months (range, 3-52 months) for surviving patients, the median survival is 32 months, and 2-year and 3-year survivals are 62%, and 39%, respectively.Radiotherapy with concomitant 5-FU by protracted venous infusion as adjuvant treatment for resected pancreatic cancer is well tolerated. This approach allows for greater dose intensity with reduced toxicity. The median survival of this cohort of patients compares favorably with our earlier experience and other published series.

    View details for Web of Science ID 000165604600030

    View details for PubMedID 11121652

  • Chemo-radiotherapy for localized pancreatic cancer: Increased dose intensity and reduced acute toxicity with concomitant radiotherapy and protracted venous infusion 5-fluorouracil INTERNATIONAL JOURNAL OF RADIATION ONCOLOGY BIOLOGY PHYSICS Poen, J. C., Collins, H. L., Niederhuber, J. E., Oberhelman, H. A., Vierra, M. A., Bastidas, A. J., Young, H. S., Slosberg, E. A., Jeffrey, B. R., Longacre, T. A., Fisher, G. A., Goffinet, D. R. 1998; 40 (1): 93-99

    Abstract

    Although concomitant radiation therapy (RT) and bolus 5-Fluorouracil (5-FU) have been shown to improve survival in locally confined pancreatic cancer, most patients will eventually succumb to their disease. Since 1994, we have attempted to improve efficacy by administering 5-FU as a protracted venous infusion (PVI). This study compares treatment intensity and acute toxicity of consecutive protocols of concurrent RT and 5-FU by bolus injection or PVI.Since 1986, 74 patients with resected or locally advanced pancreatic cancer were treated with continuous course RT and concurrent 5-FU by bolus injection (n = 44) or PVI throughout the course of RT (n = 30). Dose intensity was assessed for both 5-FU and radiotherapy. Toxicity endpoints which could be reliably and objectively quantified (e.g., neutropenia, weight loss, treatment interruption) were evaluated.Cumulative 5-FU dose (mean = 7.2 vs. 2.5 gm/m2, p < 0.001) and weekly 5-FU dose (mean = 1.3 vs. 0.5 gm/m2/wk, p < 0.001) were significantly higher for patients receiving PVI 5-FU. Following pancreaticoduodenectomy, 95% of PVI patients maintained a RT dose intensity of > or = 900 cGy/wk, compared with 63% of those receiving bolus 5-FU (p = 0.02). No difference was seen for patients with locally advanced disease (72% vs. 76%, p = n.s.). Grade II-III neutropenia was less common for patients treated with PVI (13% vs. 34%, p = 0.05). Grade II-III thrombocytopenia was uncommon (< or = 3%) in both treatment groups. Mean percent weight loss (3.8% vs. 4.1%, p = n.s.) and weight loss > or = 5% of pre-treatment weight (21% vs. 31%, p = n.s.) were similar for PVI and bolus treatment groups, respectively. Treatment interruptions for hematologic, gastrointestinal or other acute toxicities were less common for patients receiving PVI 5-FU (10% vs. 25%, p = 0.11).Concurrent RT and 5-FU by PVI was well tolerated and permitted greater chemotherapy and radiotherapy dose intensity with reduced hematologic toxicity and fewer treatment interruptions compared with RT and bolus 5-FU. Longer follow-up will be needed to assess late effects and the impact on overall survival.

    View details for Web of Science ID 000071164200015

    View details for PubMedID 9422563

  • PSEUDOMYXOMA PERITONEI SURGERY GYNECOLOGY & OBSTETRICS Fann, J. I., Vierra, M., Fisher, D., Oberhelman, H. A., Cobb, L. 1993; 177 (5): 441-447

    Abstract

    Pseudomyxoma peritonei results from implantation of malignant tumors or irritation from ruptured benign cysts. This disease is traditionally characterized by accumulation of mucinous ascites, relatively long survival period and absence of extraperitoneal metastases. Disease progression is difficult to predict because of the spectrum of underlying pathologic entities. Four unusual instances of pseudomyxoma peritonei are presented. An instance of the neoplasm confined to the splenic parenchyma suggests potential for hematogenous dissemination. The tumor can be limited to and extend along the retroperitoneum. Retained rectal tissue after proctocolectomy may be a possible origin of disease. Enterobronchial fistula formation is a serious long term complication. Aggressive surgical approach with resection of the bulk of disease offers the optimal palliation and prognosis.

    View details for Web of Science ID A1993MF15300001

    View details for PubMedID 8211593

  • A REAPPRAISAL OF THE KOCK CONTINENT ILEOSTOMY IN PATIENTS WITH CROHNS-DISEASE SURGERY GYNECOLOGY & OBSTETRICS Bloom, R. J., Larsen, C. P., Watt, R., Oberhelman, H. A. 1986; 162 (2): 105-108

    Abstract

    The diagnosis of Crohn's disease has been considered a contraindication to the construction of a Kock continent ileostomy. From 1975 to 1984, 95 Kock continent ileostomies were performed at the Stanford University Medical Center. The clinical course of seven patients with regional enteritis who were disease-free for five years was reviewed. All of the patients studied were women, with a mean disease-free interval of 7.7 years and a range of follow-up study of four to 50 months. To date, all of the patients are fully continent to gas and ileal effluent. The postoperative complication and revision rate (28 per cent) was comparable with the results cited in the literature for individuals with ulcerative colitis or familial polyposis. When revisions were necessary, patients elected to keep the Kock pouch rather than conversion to a conventional Brooke ileostomy. The authors agree that active regional enteritis is to be considered a contraindication to the construction of a continent ileostomy. However, the benefits afforded a patient with a continent ileal reservoir are substantial and warrant consideration in a select group of patients with Crohn's disease who are disease-free for a minimum of five years.

    View details for Web of Science ID A1986AYW5300001

    View details for PubMedID 3484841

  • SEGMENTAL EFFECT OF LUMBAR EPIDURAL HYDROMORPHONE - A CASE-REPORT ANESTHESIOLOGY HORAN, C. T., BEEBY, D. G., Brodsky, J. B., Oberhelman, H. A. 1985; 62 (1): 84-85

    View details for Web of Science ID A1985AAQ6500019

    View details for PubMedID 2578261

  • INFLAMMATORY DISEASE OF BOWEL - INDICATIONS FOR SURGERY DISEASES OF THE COLON & RECTUM Oberhelman, H. A. 1976; 19 (7): 582-583

    View details for Web of Science ID A1976CK21100004

    View details for PubMedID 1086195

Conference Proceedings


  • Preoperative chemoradiation for marginally resectable adenocarcinoma of the pancreas Mehta, V. K., Fisher, G., Ford, J. A., Poen, J. C., Vierra, M. A., Oberbelman, H., Niederhuber, J., Bastidas, J. A. SPRINGER. 2001: 27-35

    Abstract

    Only 10% to 20% of patients with pancreatic cancer are considered candidates for curative resection at the time of diagnosis. We postulated that preoperative chemoradiation therapy might promote tumor regression, eradicate nodal metastases, and allow for definitive surgical resection in marginally resectable patients. The objective of this study was to evaluate the effect of a preoperative chemoradiation therapy regimen on tumor response, resectability, and local control among patients with marginally resectable adenocarcinoma of the pancreas and to report potential treatment-related toxicity. Patients with marginally resectable adenocarcinoma of the pancreas (defined as portal vein, superior mesenteric vein, or artery involvement) were eligible for this protocol. Patients received 50.4 to 56 Gy in 1.8 to 2.0 Gy/day fractions with concurrent protracted venous infusion of 5-fluorouracil (250 mg/m2/day). Reevaluation for surgical resection occurred 4 to 6 weeks after therapy. Fifteen patients (9 men and 6 women) completed preoperative chemoradiation without interruption. One patient required a reduction in the dosage of 5-fluorouracil because of stomatitis. Acute toxicity from chemoradiation consisted of grade 1 or 2 nausea, vomiting, diarrhea, stomatitis, palmar and plantar erythrodysesthesia, and hematologic suppression. CA 19-9 levels declined in all nine of the patients with elevated pretreatment levels. Nine of the 15 patients underwent a pancreaticoduodenectomy, and all had uninvolved surgical margins. Two of these patients had a complete pathologic response, and two had microscopic involvement of a single lymph node. With a median follow-up of 30 months, the median survival for resected patients was 30 months, whereas in the unresected group median survival was 8 months. Six of the nine patients who underwent resection remain alive and disease free with follow-up of 12, 30, 30, 34, 39, and 72 months, respectively. Preoperative chemoradiation therapy is well tolerated. It may downstage tumors, sterilize regional lymph nodes, and improve resectability in patients with marginally resectable pancreatic cancer. Greater patient accrual and longer follow-up are needed to more accurately assess its future role in therapy.

    View details for Web of Science ID 000167919800010

    View details for PubMedID 11309645

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