Sertoli-Leydig cell tumour complicated by X chromosomal mosaicism

We describe a case of well-differentiated Sertoli-Leydig cell tumour (SLCT) of the ovary. A 48-year-old Japanese woman had had symptoms of virilization, i.e. alopecia and facial hair, for 8 years. Although the patient had given birth to three normal children, laboratory investigations revealed an elevated serum level of free testosterone and tripartite mosaicism (45X/46XX/47XXX). Computed tomography and magnetic resonance imaging revealed a tumour of the left ovary. After oophorectomy, the serum level of free testosterone returned to the normal range and symptoms of virilization resolved. To our knowledge, this is the first reported case of a patient with SLCT who had tripartite mosaicism and had given birth to normal children. Although the aetiology of SLCT is not known, we believe that SLCT is associated with sex chromosomal abnormalities at least in some cases.