Experience with the use of olaparib in patients with ovarian cancer

Introduction: More than the twenty percent of ovarian cancers are hereditary, and most have BRCA mutations. The 30% of Mexican patients with the BRCA1 mutation have the BRCA1 gene exon 9-12del deletion founder mutation (BRCA1 ex9-12del). BRCA-mutated tumors are more sensitive to PARP inhibitors such as olaparib. Objective: To show the clinical experience on the use of olaparib at Instituto Nacional de Cancerologia in Mexico. Method: Ovarian cancer patients treated with olaparib from November 2016 to December 2018 were studied, and their characteristics, clinical response, progression-free survival (PFS) and toxicities were described. Results: Nineteen patients were assessed, with BRCA1 mutation being found in 78.9%, out of which 21.1% were carriers of the ex9-12del founder mutation. The median of PFS was 12 months; for patients treated on second and third line it was greater than 15 months, and for those treated with a fourth and subsequent line it was 8.3 months. Patients with the founder mutation had better results. Toxicities were like those reported in previous studies. Conclusions: Olaparib offers greater PFS benefit as maintenance therapy after a first and second relapse. Patients with founder mutation have had sustained PFS.