Investigator

David D’Souza

Physician · Western University, Oncology

DDDavid D’Souza
Papers(2)
Adjuvant carboplatin …A Phase II Randomized…
Collaborators(10)
Douglass VinesJeffrey P. BruceJennifer CrokeKathy HanMarianne KoritzinskyMarjan RouzbahmanMelania PintilieMichael MilosevicMorgan BlackNaz Chaudary
Institutions(4)
Victoria Hospital Htt…Princess Margaret Can…University Health Net…University Of Toronto

Papers

Adjuvant carboplatin and paclitaxel with “sandwich” method radiotherapy for stage III or IV endometrial cancer: long-term follow-up at a single-institution

To evaluate disease-free survival (DFS) and overall survival (OS) associated with adjuvant carboplatin and paclitaxel chemotherapy interposed with radiation for advanced endometrial cancer. This is a cohort study of adult women with stage III or IV endometrial cancer treated at a single institution, between April 2002 and October 2017. Tumor and treatment characteristics were recorded. Treatment consisted of 4 cycles of intravenous paclitaxel and carboplatin every 3 weeks, followed by external beam radiotherapy to the pelvis (45-50 Gy), and another 2 cycles of chemotherapy. One cohort of patients were prospectively enrolled from 2002 through 2006 and an additional cohort from 2007 to 2017, which was retrospectively analyzed. Primary endpoints for this study were DFS and OS rates which were calculated using Cox regression models. Eighty-two patients with a median age of 66.5 years (range, 35-83 years) were included. Median follow-up was 46 months (range, 9-196 months). Most patients had stage IIIC disease (62.2%) and serous carcinoma histology (46.3%). Median OS was 146 months and median DFS was 71 months. A 5-year OS and DFS were 64.9% and 55.7%, respectively. Age >60 years subgroup was at a significantly higher risk of DFS event or death. Histological subtype, location of positive nodes, and cancer stage (IIIa vs. higher stage) did not correlate to a higher risk of recurrence or death. Long term follow-up and a larger population confirm that the chemoradiotherapy sandwich method yields favorable outcomes in patients with high-risk endometrial cancer.

A Phase II Randomized Trial of Chemoradiation with or without Metformin in Locally Advanced Cervical Cancer

Abstract Purpose: Tumor hypoxia is associated with poor response to radiation (RT). We previously discovered a novel mechanism of metformin: enhancing tumor RT response by decreasing tumor hypoxia. We hypothesized that metformin would decrease tumor hypoxia and improve cervical cancer response to RT. Patients and Methods: A window-of-opportunity, phase II randomized trial was performed in stage IB–IVA cervical cancer. Patients underwent screening positron emission tomography (PET) imaging with hypoxia tracer fluoroazomycin arabinoside (FAZA). Only patients with FAZA uptake (hypoxic tumor) were included and randomized 2:1 to receive metformin in combination with chemoRT or chemoRT alone. A second FAZA-PET/CT scan was performed after 1 week of metformin or no intervention (control). The primary endpoint was a change in fractional hypoxic volume (FHV) between FAZA-PET scans, compared using the Wilcoxon signed-rank test. The study was closed early due to FAZA availability and the COVID-19 pandemic. Results: Of the 20 consented patients, 6 were excluded due to no FAZA uptake and 1 withdrew. FHV of 10 patients in the metformin arm decreased by an average of 10.2% (44.4%–34.2%) ± SD 16.9% after 1 week of metformin, compared with an average increase of 4.7% (29.1%–33.8%) ± 11.5% for the 3 controls (P = 0.027). Those with FHV reduction after metformin had significantly lower MATE2 expression. With a median follow-up of 2.8 years, the 2-year disease-free survival was 67% for the metformin arm versus 33% for controls (P = 0.09). Conclusions: Metformin decreased cervical tumor hypoxia in this trial that selected for patients with hypoxic tumor. See related commentary by Lyng et al., p. 5233

2Papers
23Collaborators

Positions

Physician

Western University · Oncology

Education

1995

MD

University of Toronto · Medicine