- Radiation Oncology
Clinical Professor, Radiation Oncology - Radiation Therapy
Residency: UCSF Radiation Oncology Residency (1992) CA
Fellowship: Stanford University Dept of Radiation Oncology (1993) CA
Internship: UCSF Internal Medicine Residency (1988) CA
Medical Education: University of California at San Francisco School of Medicine (1987) CA
Board Certification: Radiation Oncology, American Board of Radiology (1992)
- Independent Studies (6)
- A randomized phase II study comparing surgical excision versus NeOadjuvant Radiotherapy followed by delayed surgical excision of Ductal carcinoma In Situ (NORDIS) AMER ASSOC CANCER RESEARCH. 2020
Representation of Women Among Invited Speakers at Medical Specialty Conferences.
Journal of women's health (2002)
Background: Gender-related differences have been found among invited speakers in select professional and medical societies. We examined whether similar disparities existed among keynote speakers, plenary speakers, and invited lecturers in a broad range of medical specialty conferences from 2013 to 2017. Materials and Methods: A cross-sectional study was performed on 27 U.S. medical specialty conferences for which data were available on plenary speakers, keynote speakers, and/or invited lecturers. For each speaker, gender and degree(s) were determined. Fisher's exact test was performed to compare proportions of women among speakers to Association of American Medical Colleges' (AAMC) physician workforce data on gender distribution. Results: In aggregate, we identified 246 women among 984 speakers, significantly lower than expected when compared with 2015 AAMC data (25.0% vs. 34.0%; p<0.00001). Compared with AAMC data reported in 2013, 2015, and 2017, women were significantly underrepresented in 2013 (p=0.0064) and 2015 (p=0.00004). In 2017, the proportion of women among invited speakers trended lower than AAMC active women physicians but did not reach significance (p=0.309). Analysis of individual conference data stratified by year indicated that, while the representation of women among all speakers improved between 2015 and 2017, the representation of women among keynote speakers, plenary speakers, and invited lectureships was variable (including zero levels some years during the study period) and remained lower than expected as compared with workforce data for specific medical specialties. Conclusions: Evaluating for and improving disparities is recommended to ensure gender equity among invited speakers across all medical specialty conferences.
View details for DOI 10.1089/jwh.2019.7723
View details for PubMedID 31687866
Observe, and Keep Chemotherapy Up the Sleeve
INTERNATIONAL JOURNAL OF RADIATION ONCOLOGY BIOLOGY PHYSICS
2018; 100 (3): 550
View details for PubMedID 29413268
Treatment of hormone-refractory prostate cancer with Y-90-CYT-356 monoclonal antibody
CLINICAL CANCER RESEARCH
1996; 2 (8): 1289-1297
A Phase I dose-escalation study using 90Y-CYT-356 monoclonal antibody was performed in 12 patients with hormone-refractory prostate carcinoma. Biodistribution studies using 111In-CYT-356 were performed 1 week before 90Y-CYT-356 administration. Of the 12 patients, 58% had at least one site of disease imaged after administration of 111In-CYT-356. The dose of 90Y ranged from 1.83-12 mCi/m2. Both 111In and 90Y-CYT-356 were tolerated well, without significant nonhematological toxicity. Myelosuppression was the dose-limiting toxicity and occurred at dose levels of 4.5-12 mCi/m2. Of the patients receiving =9 mCi/m2, 55% had grade 1 or 2 leukopenia and/or thrombocytopenia. Two of three patients treated with 12 mCi/m2 experienced grade 3 thrombocytopenia and leukopenia. One patient treated with 12 mCi/m2 had grade 4 neutropenia. The maximum tolerated dose of 90Y-CYT-356 was 9 mCi/m2. Only one patient developed a human anti-mouse antibody 4 weeks after treatment. No patient attained a complete or partial response based on prostate-specific antigen and/or radiological criteria. Three patients had transient subjective improvement in the symptomatology of their disease. In addition, patients treated with 12 mCi/m2 of 90Y-CYT-356 had a slightly longer freedom from disease progression than patients treated with doses of 90Y-CYT-356 =9 mCi/m2.
View details for Web of Science ID A1996VB19900006
View details for PubMedID 9816299
Yttrium-90-labeled anti-CD20 monoclonal antibody therapy of recurrent B-cell lymphoma
CLINICAL CANCER RESEARCH
1996; 2 (3): 457-470
A Phase I/II dose escalation study of 90Y-murine anti-CD20 monoclonal antibody (mAb) in patients with recurrent B-cell lymphoma was performed. The primary objectives of the study were: (a) to determine the effect of the preinfusion of unlabeled anti-CD20 mAb on the biodistribution of 111In-anti-CD20 mAb; (b) to determine the maximal tolerated dose of 90Y-anti-CD20 mAb that does not require bone marrow transplantation; and (c) to evaluate the safety and antitumor effect of 90Y-anti-CD20 mAb in patients with recurrent B-cell lymphoma. Eighteen patients with relapsed low- or intermediate-grade non-Hodgkin's lymphoma were treated. Biodistribution studies with 111In-anti-CD20 mAb were performed prior to therapy. Groups of three or four patients were treated at dose levels of approximately 13.5, 20, 30, 40, and 50 mCi 90Y-anti-CD20 mAb. Three patients were retreated at the 40-mCi dose level. The use of unlabeled antibody affected the biodistribution favorably. Nonhematological toxicity was minimal. The only significant toxicity was myelosuppression. The overall response rate following a single dose of 90Y-anti-CD20 mAb therapy was 72%, with six complete responses and seven partial responses and freedom from progression of 3-29+ months following treatment. Radioimmunotherapy with =50 mCi 90Y-anti-CD20 mAb resulted in minimal nonhematological toxicity and durable clinical responses in patients with recurrent B-cell lymphoma. Doses of =40 mCi 90Y-anti-CD20 mAb were not myeloablative.
View details for Web of Science ID A1996TY62000004
View details for PubMedID 9816191
Treatment of cutaneous T-Cell lymphoma with chimeric anti-CD4 monoclonal antibody
1996; 87 (3): 893-899
Chimeric anti-CD4 monoclonal antibody was administered intravenously as a single dose to eight patients with mycosis fungoides. The dose was escalated throughout the study between patients groups, and individual patients received 50, 100, or 200 mg per dose. Seven of eight patients responded to treatment with an average freedom from progression of 25 weeks (range, 6 to 52 weeks). The treatment was well tolerated, and there was no clinical evidence of immunosuppression. Following treatment, there was significant suppression of peripheral blood CD4 counts in all patients for 1 to 22+ weeks. Only one patient made a very low titer human antichimeric antibody response. All but two patients made primary antibody and T-cell proliferative responses to a foreign antigen administered 24 hours after antibody infusion. However, there was generally marked, but temporary suppression of T-cell proliferative responses in vitro to phytohemagglutinin (PHA), tetanus toxoid, and normal donor lymphocytes. We conclude that at the dose levels studied, this antibody (1) had clinical efficacy against mycosis fungoides; (2) was well tolerated; (3) had a low level of immunogenicity; (4) decreased T-cell proliferative responses in vitro, and (5) did not induce tolerance to a foreign antigen.
View details for Web of Science ID A1996TT48400008
View details for PubMedID 8562959
MUSCLE CRAMPING IN PHASE-I CLINICAL-TRIALS OF TIRAPAZAMINE (SR-4233) WITH AND WITHOUT RADIATION
8th International Conference on Chemical Modifiers of Cancer Treatment
PERGAMON-ELSEVIER SCIENCE LTD. 1994: 379–82
Tirapazamine (SR 4233) is a benzotriazine di-N-oxide which acts as a hypoxic cytotoxic agent and as a radiation enhancer when given shortly before or after radiation. Three Phase I clinical trials were designed to determine the maximum tolerated dose, toxicities, pharmacokinetics, and effects on irradiated tumors and normal tissues.Tirapazamine 9 mg/m2 to 21 mg/m2 was given i.v. 1/2 to 1 h prior to irradiation on a multiple dose schedule of 10 consecutive doses. This was later revised to a three times-per-week schedule for 12 doses. In a second clinical trial, tirapazamine was given in a single dose of 18 mg/m2 to 293 mg/m2 i.v. after irradiation. In a third trial, tirapazamine was administered without irradiation in single doses of 36 mg/m2 to 250 mg/m2, with an option for retreatment.Subjects reported muscle cramping of varying degrees of severity on all three dose schedules. One patient experienced Grade 3 cramping and treatment was discontinued. The most frequent site of cramping were the lower extremities. Creatine phosphokinase (CPK) values were elevated in three patients with associated muscle soreness in one patient. MB (cardiac) isoenzymes were elevated in one patient with no evidence of cardiac muscle damage, and returned to baseline at drug completion. No consistent abnormalities in clinical laboratory values were found. Stretching of the muscle was most effective in relieving the cramping.Muscle cramping has been the most frequently reported toxicity in Phase I studies of tirapazamine, though it does not appear to be dose limiting. Dose escalation on the three clinical trials continues. In vitro studies to investigate the cramping are ongoing.
View details for Web of Science ID A1994NN51200028
View details for PubMedID 8195037
EFFECT OF FILGRASTIM (G-CSF) IN HODGKINS-DISEASE PATIENTS TREATED WITH RADIATION
INTERNATIONAL JOURNAL OF RADIATION ONCOLOGY BIOLOGY PHYSICS
1994; 28 (2): 445-450
To evaluate the effect of filgrastim (recombinant human G-CSF) on radiation-induced neutropenia in a well defined, homogenous patient population.Seven patients who were to receive large field subdiaphragmatic irradiation after thoracic "mantle" fields for treatment of Hodgkin's disease entered this study. They received daily subcutaneous (SC) injections of filgrastim during subdiaphragmatic irradiation. Total white blood cell (WBC) and absolute neutrophil cell (ANC) counts were measured and compared to a historical series of patients, and hematological toxicity was assessed. The endpoints of the study were nadir WBC and ANC counts and time to WBC and ANC recovery.Compared to the historical series, filgrastim significantly increased the WBC and ANC throughout the period of subdiaphragmatic irradiation. Nadir WBC (5.98 +/- 1.24/mm3) and ANC (4.71 +/- 1.07/mm3) in the Filgrastim group were approximately two times those of the historical series (3.32 +/- 1.06/mm3 and 2.39 +/- 0.97/mm3 respectively; p < 0.002). Nadir platelet counts were not affected by filgrastim therapy. Three of seven patients reported mild musculoskeletal pain, but there was no other apparent toxicity.Compared to the historical series, filgrastim therapy significantly increased WBC and ANC during extended field radiation therapy and was well tolerated. It may be clinically useful in other groups of patients who are likely to develop profound neutropenia during large field irradiation.
View details for Web of Science ID A1994MP98100015
View details for PubMedID 7506247