Introduction/Background This study aimed to find the incidence of occult malignancy (precursor lesions and cancer) after RRSO in BRCA1/2 carriers due to most BRCA1/2 carriers do not undergo RRSO by the recommended age.

Methodology We retrospectively reviewed patients identified as BRCA mutation carriers who underwent RRSO at Hospital de la Santa Creu i Sant Pau, Barcelona, Spain, from 1993 to 2023. Of all the patients, we analyzed the objective examination, CA 125 values and transvaginal ultrasound preoperatively. All cases were examined according to the Sectioning and Extensively Examining the Fimbria (SEE/FIM) protocol and underwent immunohistochemically staining

Results RRSO was performed in 100 patients in our Hospital. All patients were asymptomatic with normal physical exams. The median age at RRSO was 50.48 years (range 35 to 81 years). Among these carriers of BRCA1, BRCA2 and both mutations with the average age were respectively 60 (49.43 years), 39 (52.25 years) and 1 (44 years) at the surgery. According to literature, the detection rate of precursor lesions or cancer was 4% (4/100). In particular of the patients cohort, 3 showed serous tubal intraepithelial carcinoma (STIC), and 1 showed occult cancer of tubal origin. All occult lesions cases were detected in patients older than 44 years. In the analysis according to age, precursor lesions or cancer were detected only in BRCA1 mutation carriers, with a prevalence of 1.04% of HGSC at RRSO in BRCA1, confirming the possible faster occurrence of precursor lesions or cancer in BRCA1 mutation carriers.

Conclusion Our findings support the significance of RRSO particularly if surgery is performed above the target age. A rigorous surgical protocol with meticulous pathologic review at RRSO yielded an overall detection rate of 4% for occult gynecological carcinoma in BRCA mutation carriers followed by a multidisciplinary team at a single institution.

Disclosures Authors have no conflict of interest to declare.