The presentation of an asymptomatic ovarian carcinosarcoma caught by BRCA1 mutation surveillance program

Women with the BRCA1/2 mutations, which cause hereditary breast and ovarian cancer (HBOC), are 35–40 times more likely to develop ovarian cancer compared with the general population. We treated a patient in whom ovarian carcinosarcoma was identified during surveillance for HBOC. She had suffered from breast cancer at ages 45 and 50. At the age of 54 years, she was diagnosed as carrying an “uncertain significant” BRCA1 variant using a genetic mutation analysis. She was referred to our department, and surveillance was performed every 3–6 months for BRCA1 pathogenic mutation carriers due to her family history. At the age of 62 years, cervical and endometrial cytology suggested a diagnosis of adenocarcinoma. At this point, the CA125 level was 19.7 and positron emission tomography/computed tomography (PET/CT) images revealed a right ovarian tumor (SUV max , 7.41). Surgery was performed, and ovarian carcinosarcoma (pT3cN0M0) was diagnosed. Adjuvant chemotherapy consisting of paclitaxel and carboplatin was initiated. In the month during which the cancer was identified, BRCA1 variant mutation was re-designated as “suspected deleterious,” and 8 years after the initial genetic diagnosis, the causative mutation was identified. The patient has been disease-free for 4 years since surgery. This case demonstrates both the importance and difficulty of surveillance.