Bio

Clinical Focus


  • Nuclear Medicine

Education & Certifications


  • Fellowship:Stanford University Radiology Fellowships (1988) CA
  • Residency:Stoke Mandeville Hospital (1982)
  • Medical Education:University of London Medical School (1980) United Kingdom
  • Board Certification: Nuclear Medicine, American Board of Nuclear Medicine (1988)
  • Residency:University Of Capetown (1985) South Africa
  • Residency:Univ Of Zimbabwe (1983)
  • Internship:Univ Coll Hospital-London (1981)

Teaching

2019-20 Courses


Publications

All Publications


  • Results from a Phase 1 Study of Sodium Selenite in Combination with Palliative Radiation Therapy in Patients with Metastatic Cancer. Translational oncology Knox, S. J., Jayachandran, P., Keeling, C. A., Stevens, K. J., Sandhu, N., Stamps-DeAnda, S. L., Savic, R., Shura, L., Buyyounouski, M. K., Grimes, K. 2019; 12 (11): 1525?31

    Abstract

    In preclinical studies, selenite had single agent activity and radiosensitized tumors in vivo. Here we report results from a Phase 1 trial in 15 patients with metastatic cancer treated with selenite (5.5 to 49.5 mg) orally as a single dose 2 hours before each radiation therapy (RT) treatment. Patients received RT regimens that were standard of care. The primary objective of the study was to assess the safety of this combination therapy. Secondary objectives included measurement of pharmacokinetics (PK) and evaluation of efficacy. Endpoints included assessment of PK, toxicity, tumor response, and pain before and after treatment. The half-life of selenite was 18.5 hours. There were no adverse events attributable to selenite until the 33 mg dose level, at which the primary toxicities were grade 1 GI side effects. One patient treated with 49.5 mg had grade 2 GI toxicity. Although this was not a DLT, it was felt that the highest acceptable dose in this patient population was 33 mg. Most patients had stabilization of disease within the RT fields, with some demonstrating objective evidence of tumor regression. Most patients had a marked improvement in pain and seven out of nine patients with prostate cancer had a decrease in PSA ranging from 11-78%. Doses up to 33 mg selenite were well tolerated in combination with RT. A randomized, well controlled study is needed at the 33 mg dose level to determine if selenite results in clinically meaningful improvements in the response to palliative RT.

    View details for DOI 10.1016/j.tranon.2019.08.006

    View details for PubMedID 31454725

  • PARATHYROID IMAGING - USE OF DUAL ISOTOPE SCINTIGRAPHY FOR THE LOCALIZATION OF ADENOMAS BEFORE SURGERY CLINICAL NUCLEAR MEDICINE Basso, L. V., Keeling, C., Goris, M. L. 1992; 17 (5): 380-383

    Abstract

    Seventy-nine patients with primary hyperparathyroidism, whose average preoperative blood calcium level was 11.6 mg/dl, underwent thallium-technetium dual isotope scintigraphy of the thyroid and parathyroids. For patients who had surgery, the detection and localization rate of parathyroid disease or the sensitivity was low (0.53), but the positive predictive value for the location was high (0.80). Correct localization correlated positively with the weight of the tumor but not significantly with the parathyroid hormone blood level nor with the blood calcium level. Unprocessed data alone were sufficient to predict correctly the location in two thirds of the detected cases. Computer processing increased the sensitivity without decreasing the specificity. Those results, at variance with earlier published data but congruent with another more recent study, require a reevaluation of the role of this scintigraphic technique in the management of hyperparathyroidal patients.

    View details for Web of Science ID A1992HT61000009

    View details for PubMedID 1316819

  • PARATHYROID IMAGING JOURNAL OF NUCLEAR MEDICINE Goris, M. L., Basso, L. V., Keeling, C. 1991; 32 (5): 887-889

    View details for Web of Science ID A1991FL18300037

    View details for PubMedID 1827150

  • HYPERTHYROIDISM WITH LOW RADIOIODINE UPTAKE AFTER HEAD AND NECK IRRADIATION FOR HODGKINS-DISEASE JOURNAL OF NUCLEAR MEDICINE Petersen, M., KEELING, C. A., McDougall, I. R. 1989; 30 (2): 255-257

    View details for Web of Science ID A1989T060300020

    View details for PubMedID 2738654

  • THE INVIVO DISTRIBUTION OF HUMAN PERIPHERAL-BLOOD LYMPHOCYTES AND LYMPHOKINE-ACTIVATED KILLER CELLS ADOPTIVELY TRANSFERRED IN HUMAN PANCREATIC-CANCER BEARING NUDE-MICE SURGERY Marincola, F. M., Drucker, B. J., KEELING, C. A., SIAO, D. Y., STARNES, H. F., Goodwin, D. A., Holder, W. D. 1989; 105 (1): 79-85

    Abstract

    In this study we evaluated human pancreatic cancer xenotransplanted into nude mice as a model suitable for adoptive immunotherapy studies. A pancreatic cancer cell line (MIA PaCa-2) was chosen and its growth in nude mice and sensitivity to lysis by human lymphokine-activated killer (LAK) cells were characterized. This line grew in 96% of the cases when young (4- to 6-week-old) Swiss/NIH nude mice were used. The line was highly sensitive to lysis by LAK cells in a standard chromium-51 release assay (67.8%), similarly to other cell lines known to be highly sensitive, such as K562 (75.6%) and the melanoma cell line SU.102 (53.1%). To assess their in vivo distribution, human peripheral blood lymphocytes (PBLs) and LAK cells were adoptively transferred into nude mice after labeling with indium-111 oxine. The results of this study show that adoptively transferred PBLs and LAK cells localize in this heterologous system as they do in autologous systems. PBLs are taken up mostly by the liver and spleen. The percentage of the administered dose of radioactivity taken up corrected by weight (percent dose per gram tissue) is 64.3 +/- 15.6%d/gm (liver) and 43.5 +/- 9.5%d/gm (spleen). LAK cells are taken up by liver (43.2 +/- 5.3%d/gm) and spleen (28.0 +/- 4.9%d/gm) but also localize significantly more than PBLs in other organs such as lungs (12.9 +/- 3.5%d/gm vs 1.4 +/- 0.3%d/gm, p less than 0.01), kidneys (19.1 +/- 2.1%d/gm vs 6.3 +/- 1.5%d/gm, p less than 0.001), and pancreatic tumors growing in orthotopic position (1.93 +/- 0.36%d/gm vs 0.56 +/- 0.06%d/gm, p less than 0.05). When the nude mice are pretreated with human recombinant tumor necrosis factor, localization of LAK cells compared with PBLs is even further enhanced both in tumors implanted in the pancreas (3.1 +/- 0.5%d/gm vs 0.56 +/- 0.06%d/gm, p less than 0.01) and in the subcutis (12.5 +/- 8.3%d/gm vs 0.95 +/- 0.29%d/gm, p less than 0.001).

    View details for Web of Science ID A1989R726300011

    View details for PubMedID 2492121

  • I-131 MIBG UPTAKE IN METASTATIC MEDULLARY CARCINOMA OF THE THYROID - A PATIENT TREATED WITH SOMATOSTATIN CLINICAL NUCLEAR MEDICINE KEELING, C. A., Basso, L. V. 1988; 13 (4): 260-263

    Abstract

    A 47-year-old man with multiple endocrine neoplasia (MEN) type 2a syndrome in whom metaiodobenzylguanidine (MIBG) concentrated in lesions from metastatic medullary carcinoma of the thyroid is reported. A somatostatin analogue (Sandostatin SMS 201-995) alleviated the symptoms of flushing and diarrhea associated with the elevated calcitonin levels but it did not alter either the course of the disease or the MIBG images. A review of the literature is presented of the noncatecholamine secreting tumors associated with MIBG uptake. Similarities between this case and metastatic carcinoid syndrome are discussed.

    View details for Web of Science ID A1988N099000007

    View details for PubMedID 2897264

  • COMPLICATIONS OF FRACTURES AND THEIR HEALING SEMINARS IN NUCLEAR MEDICINE McDougall, I. R., KEELING, C. A. 1988; 18 (2): 113-125

    Abstract

    The role of nuclear medicine studies in diagnosing late complications of fractures is described. Static bone scintigraphy is not helpful in predicting delayed or non-union of fractures. Several investigators have developed simple formulae comparing uptake in fracture site with adjacent or contralateral normal bone and described criteria that will predict problems with healing. These types of tests should only be used in patients who are at risk for delayed union. The scintigraphic diagnosis of infection complicating a fracture is difficult. Bone scintigraphy alone is not useful and combined 67Ga/99mTc MDP scanning has been disappointing. Most published series support the role in 111In WBC in this situation, but not all cases are correctly diagnosed. 111In (Chloride) cannot differentiate an infected from a delayed-healing fracture. Bone scintigraphy has a significant role in determining whether a bone graft is viable or not. Reflex sympathetic dystrophy is a rare complication of a fracture; it can be diagnosed by increased periarticular uptake on bone scan in all the joints of the affected part. Bone scintigraphy, especially when done with SPECT, is a very sensitive test for the diagnosis of avascular necrosis (AVN).

    View details for Web of Science ID A1988N448200003

    View details for PubMedID 3291125

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