Abstract
Sex cord-stromal tumors (SCSTs) are ovarian tumors that generally present with an adnexal mass and signs/symptoms of hormone excess. Gynandroblastoma is a rare subtype of SCST with a combination of female and male sex cord differentiation. These tumors typically present in premenopausal women and are diagnosed at early stages with benign clinical courses. Here, we present a rare case of recurrent gynandroblastoma in a premenopausal woman with a DICER1 germline mutation. The patient was referred to our clinic for new symptoms of hormonal imbalance with a history of ovarian juvenile granulosa cell tumor (JGCT). Evaluation revealed a 5x5cm complex right adnexal mass and rising inhibin B. Patient underwent total abdominal hysterectomy with right salpingo-oophorectomy, omentectomy and right pelvic and para-aortic lymphadenectomy. Pathology showed a right ovarian gynandroblastoma. Somatic biallelic mutations in the RNase IIIb domain of DICER1 were identified; a 23-gene germline panel confirmed a germline DICER1 pathogenic variant. Cascade testing of her children documented that both daughters inherited the pathogenic variant. Testing for DICER1 mutations has important implications for individual and familial tumor risk assessment given what we know about DICER1 mutation and increased childhood cancer risk.