Germline BRCA pathogenic variants in patients with ovarian cancer and post-poly (ADP-ribose) polymerase inhibitor myeloid neoplasms

Background: Among patients with advanced high-grade ovarian carcinoma (aHGOC) treated with poly (ADP-ribose) polymerase (PARP) inhibitors (PARPis), the presence of a germline BRCA pathogenic variant (gBRCA-PV) may increase the risk of bone marrow mutagenesis resulting in postcytotoxic therapy myelodysplastic neoplasms (MDS-pCT) or acute myeloid leukemia (AML-pCT), as it is expressed in heterozygosity also by hematopoietic progenitors. We aimed to investigate the occurrence of post-PARPi MDSs/AMLs-pCTs according to gBRCA-PV status. Patients and methods: We conducted a retrospective single-center study to evaluate MDS/AML-pCT in patients with aHGOC and a known gBRCA-PV status receiving at least 8 weeks of maintenance PARPi, in any line of therapy, from February 2017 to December 2022. The endpoint was the proportion of patients who experienced MDSs-pCT and AMLs-pCT during and after treatment with PARPi, in gBRCA-PV carriers and non-carriers. Results: A total of 166 patients were included: 95 (57%) had a gBRCA-PV and 72% received PARPi for recurrent disease. The number of lines of chemotherapies before and after PARPi, median overall survival, and median follow-up were comparable between gBRCA-PV carriers and non-carriers. After a median follow-up of 40.0 (95% confidence interval: 35.7-44.3) months, 10 (6%) patients were diagnosed with an MDS-pCT and 4 (2%) with an AML-pCT. A higher proportion of MDSs/AMLs-pCT (10% versus 2%; P = 0.16) and, in particular, of MDSs-pCT (9% versus 1%; P = 0.04) was observed among gBRCA-PV carriers. Conclusions: The presence of a gBRCA-PV is associated with a higher risk of MDS-pCT and possibly of myeloid neoplasms after PARPi in patients with aHGOC who received PARPi, especially in the setting of recurrent disease.