Carriers of the BRCA1/2 mutation who undergo risk-reducing salpingo-oophorectomy (RRSO) still face a risk of developing metachronous peritoneal carcinomatosis, according to new findings published in Cancer.
The risk was predominantly observed in BRCA1 mutation carriers, and disease development generally occurred within 5 years following RRSO. Women who underwent RRSO at an age older than that currently recommended also had a higher risk of developing peritoneal carcinoma.
Their median age was 52 years at the time they underwent surgery, and 60 years when they were diagnosed with peritoneal carcinomatosis. As compared with the control group, the patients were older at the time they underwent RRSO (P = .025).
In eight RRSO specimens that were obtained from women who subsequently developed peritoneal carcinomatosis, five (62.5%), had serous tubal intraepithelial carcinoma (STIC) and one had epithelial atypia.
“The findings of the current study can be used to refine gynecologic counseling for BRCA1/2 mutation carriers who consider risk-reducing surgery and to stress the importance of complete RRSO at the recommended ages,” wrote lead author Marline G. Harmsen, MD, PhD, of the Radboud University Medical Center, Nijmegen, the Netherlands.
BRCA1/2 mutation carriers face a higher risk of developing ovarian carcinoma, and RRSO can reduce that risk by 80%-96%. Surgery is recommended for carriers of BRCA1 mutations aged 35-40 years and for BRCA2 mutation carriers aged 40-45 years.
In this study, Dr. Harmsen and her colleagues conducted a literature search in order to collect and analyze clinical and pathological data from women with BRCA1/2 mutation who developed peritoneal carcinomatosis following RRSO. The cases that were identified were then compared with a cohort from a single institution.
Of the 36 cases that were identified, 86.1% were BRCA1 mutation carriers and the remaining 5 patients had a BRCA2 mutation. The median age at the time of surgery differed significantly between BRCA1 (51 years; range, 30-71 years) and BRCA2 mutation carriers (57 years; range, 56-65 years) (P = .006).
The majority of women had undergone salpingo-oophorectomy (31; 86.1%), and 16 (44.4%) had also had a hysterectomy.
The authors found that several statistically significant differences between the case studies and the control group: the median age surgery (52 vs. 46 years), percentage of BRCA1 mutation carriers (86.1% vs. 53.1%, P less than .001), and percentage of serous tubal intraepithelial carcinomas in the RRSO specimens (62.5% vs. 0%; P less than .001).
SOURCE: Hamsen MG et al. Cancer. 2018 Jan 9. doi: 10.1002/cncr.31211.