granulosa cell tumor (MONDO_0006036, a Monarch Disease Ontology entry) is a slow-growing, malignant tumor, characterize by the presence of granulosa-like cells and Call-Exner bodies, that is almost always found in the ovary. In rare cases, it has also been found in the testicle. There are two types of granulosa cell tumor that can be distinguished under the microscope: the adult and the juvenile. The testicular juvenile granulosa cell tumors are perhaps the most common congenital testicular neoplasms. Also known as: granulosa cell neoplasm, granulosa cell neoplasm (disease), granulosa cell tumor, adult type, granulosa cell tumor, adult type (morphologic abnormality), granulosa cell tumor, sarcomatoid, neoplasm of granulosa cell, tumor of granulosa cell, tumour of granulosa cell.