Adult type granulosa cell tumor in adult testis: report of a case and review of the literature

Granulosa cell tumors can be classified into juvenile and adult types and more commonly occur in ovaries. Adult testicular granulosa cell tumors are extremely rare and only 29 cases of adult type have previously been reported. We report here a 28-year old Caucasian man with a left testicular adult type granulosa cell tumor. The tumor measured 2.6×2.6×2.5 cm and was mitotically active (10/10 HPF). Immunohistochemical stains showed the tumor diffusely positive for inhibin and vimentin, and negative for epithelial membrane antigen, cytokeratins, synaptophysin, HMB-45, OCT-4, placental-like alkaline phosphatase and lymphoid markers. The reported granulosa cell tumors in adult testis were briefly reviewed.