ABSTRACT
The hormone-producing mesenchymomas of the ovaries can be divided into androblastomas and gynaecoblastomas. The former are derived from »male« elements, and consist of Sertoli-cell tumours and Leydig-cell tumours. The latter arise from »female« elements and consist of granulosacell tumours and theca-cell tumours. Sertoli-cell tumours and granulosacell tumours produce oestrogens, while Leydig-cell tumours and theca-cell tumours produce oestrogens or androgens. Histologically, androblastomas and gynaecoblastomas are often difficult to distinguish. Since no »female« elements occur in a testicle, a granulosa-cell tumour in a testicle is improbable. Gynandroblastomas, therefore, can only be found in an ovary.