54P Real-world data of patients with recurrent BRCA-mutated platinum-sensitive ovarian cancer treated with olaparib maintenance: Surgical outcome subgroup analysis from the C-PATROL study

Maintenance monotherapy with the poly-(ADP-ribose)-polymerase inhibitor olaparib has previously shown good effectiveness and tolerability in patients with platinum-sensitive relapsed ovarian cancer (PSROC) who are in response to platinum-based chemotherapy (PBC) in the C-PATROL study. Cytoreductive surgery followed by PBC has the potential to improve survival in PSROC if a complete resection can be achieved. The prospective German non-interventional study C-PATROL (NCT02503436) captured routine clinical data of patients with BRCA-mutated PSROC treated with PBC and receiving olaparib maintenance according to label. This predefined subgroup analysis compares patients based on surgery details for the current relapse and its outcome: patients who were macroscopic tumour-free (MTF) versus no surgery/non-MTF (non-MTF). Data were analysed by descriptive statistics. The study enrolled 277 patients between 10/2015 and 10/2019. Within the ITT set (study selection criteria fulfilled; N=267), 66 patients were included in the MTF vs 201 in the non-MTF subgroup (182 had no surgery and 19 were non-MTF). Median age was 59 vs 61 years, 58% vs 60% had an ECOG performance status of 0, 82% vs 63% were tumour-free after primary surgery, 27% vs 34% had ≥2 relapses, and 65% vs 20% had a complete response (CR) to the current PBC. Median follow-up was 42.8 (range: 0.3–80.5) vs 20.3 months (0.0–79.4). Median progression-free survival (PFS) was 43.2 (95% CI 21.9–nr) vs 12.1 months (10.7–14.1). Median overall survival (OS) was not reached (nr) (95% CI 60.8–nr) vs 27.4 months (24.4–33.6). Adverse events (AEs) were consistent with the known tolerability profile of olaparib (safety set: n=274; any AE: 96% vs 95%, AE of CTCAE grade ≥3: 34% vs 42%, olaparib discontinuation due to AE: 9% vs 12%). Patients with PSROC for whom in the real-world a macroscopic complete (recurrence)tumour-resection was achieved before receiving PBC and olaparib maintenance, have a beneficial prognosis concerning PFS and OS.