Hallmarks of BMCOC are increased sensitivity to platinum-based CT (PCT) and PARP inhibitors (PARPi). Regulatory approvals of PARPi will affect CT strategies for heavily pretreated BMCOC pts. Effectiveness of CT in this population is investigated.
BMCOC pts who received CT from 2006-2016 at 4 cancer centers in Spain were retrospectively selected. OS and time to progression (TTP) were calculated with Kaplan Meier and Cox models.
Out of 135 BMCOC pts identified (63% BRCA1; 37% BRCA2; 6 pts somatic), 87 (64%) had recurrent disease. After a median follow-up of 6 years, OS rate was 67% in BRCA1 and 66% in BRCA2 pts (p = 0.98). Median treatment lines after relapse was 4 (2-7); 42 pts (48%) were exposed to PARPi. At 3rd relapse, 78% pts remained platinum-sensitive (P-S). Out of 156 treatments given to 57 pts who had ≥3 treatment lines, 44% were PCT, 27% non-PCT, 14% PARPi and 15% PCT plus PARPi. Across all treatment lines, median TTP was 10.2 m (CI95% 8.4-11.9). In P-S context, TTP was improved with PCT plus PARPi (17.1 m), PCT (12.6 m) or PARPi (12.4 m) vs non-PCT (4.9 m, p 0.4 all comparisons). Multivariate model (BRCA1/2 status, treatment line and prior PARPi) confirmed platinum sensitivity as the strongest predictor for longer TTP beyond 2nd relapse (HR 0.28; p
Heavily pretreated BMCC demonstrated increased CT sensitivity, including for non-PCT choices. In P-S setting, either PCT rechallenge (+/- PARPi) or PARPi monotherapy represent the best treatments options. PARPi exposure does not compromise benefit to subsequent CT. In this population, platinum-sensitivity remains the main prognostic factor to predict CT benefit.
Clinical trial identification
Legal entity responsible for the study
Vall d’Hebron University Hospital Institute of Oncology (VHIO)
A. Oaknin: Membership on advisory board or board of directors: Roche, Astra-Zeneca, Clovis, PharmaMar. All other authors have declared no conflicts of interest.