Objectives To evaluate the safety and efficacy of olaparib in treatment of patients with BRCA 1/2 mutated relapsed epithelial ovarian cancer.

Methods Retrospective analysis of patients with BRCA 1/2 mutated relapsed epithelial ovarian cancer treated with olaparib at the Institute of Oncology Ljubljana in the period from Nov 2015 to Dec 2020.

Results In the observed period, a total of 88 patients with BRCA 1/2 mutated relapsed epithelial ovarian cancer were treated with olaparib. Median age of patients was 60 years. Majority of patients (61%) had 1st relapse of the disease. Majority of patients (74%) had germline BRCA 1 gene mutation. Majority of patients (85%) had at least one adverse event during olaparib treatment. The most common adverse events (all grades) were: nausea (59%), fatigue (59%), anemia (25%), dispepsia (14%), diarrhea (11%), dysgeusia (10%), neutropenia (6%) and arrhythmia (1%). Severe adverse events (grade 3/4) had 10% of patients: anemia 9%, nausea 1%. Median follow up was 40 months. Median PFS was 14,3 months, median OS was 20,4 months. PFS was in correlation to the type of BRCA gene mutation: 80% of patients with somatic BRCA 1/2 gene mutation were progression-free, 55% of patients with germline BRCA 2 gene mutation were progression-free, while 32% of patients with germline BRCA 1 gene mutation were progression-free (p=0,021). The type fo BRCA 1/2 gene mutation did not correlate with OS.

Conclusions Analysis shows olaparib is safe and effective maintainance treatment in BRCA1/2 relapsed epithelial ovarian cancer with results that a comparable to those published in Study19 and SOLO-2.