Background: Approximately 10-15% of ovarian carcinomas (OC) are attributed to inherited susceptibility, the majority of which are due to mutations in BRCA1 or BRCA2 (BRCA1/2). These patients display superior clinical outcome, including enhanced sensitivity to platinum-based chemotherapy. Here, we seek to investigate whether BRCA1/2 status influences the response rate to single-agent pegylated liposomal doxorubicin (PLD) in high grade serous (HGS) OC.
Methods: One hundred and forty-eight patients treated with single-agent PLD were identified retrospectively from the Edinburgh Ovarian Cancer Database. DNA was extracted from formalin-fixed paraffin-embedded (FFPE) archival tumour material and sequenced using the Ion Ampliseq BRCA1 and BRCA2 panel. A minimum variant allele frequency threshold was applied to correct for sequencing artefacts associated with formalin fixation.
Results: A superior response rate to PLD was observed in patients with HGS OC who harboured variants likely to affect BRCA1 or BRCA2 function compared to the BRCA1/2 wild-type population (36%, 9 of 25 patients versus 12.1%, 7 of 58 patients; p = 0.016). An enhanced response rate was also seen in patients harbouring only the BRCA1 SNP rs1799950, predicted to be detrimental to BRCA1 function (50%, 3 of 6 patients versus 12.1%, 7 of 58 patients; p = 0.044).
Conclusions: These data demonstrate that HGS OC patients with BRCA1/2 variants predicted damaging to protein function experience superior sensitivity to PLD, consistent with impaired DNA repair. Further characterisation of rs1799950 is now warranted in relation to chemosensitivity and susceptibility to developing ovarian carcinoma.
Keywords: BRCA1; BRCA2; Ovarian cancer; PLDH.