Ovary, Adult-type granulosa cell tumour

Adult-type granulosa cell tumour is a neoplastic proliferation comprised of at least 10% granulosa cells in a fibrothecomatous background. Generally, these are unilateral (greater than 95% of the time) with a yellow to white cut surface and can present with estrogenic manifestations in up to 2/3 of cases.

Microscopically, a variety of patterns can be present including: diffuse, trabecular, microfollicular, macrofollicular, insular, gyriform, watered silk and pseudopapillary. Occasionally, these tumours form pathognomonic fluid filled structures called Call-Exner bodies. Tumour cells have scant eosinophilic cytoplasm and round to oval nuclei with a longitudinal groove (so called “coffee bean” nuclei). They display minimal cytologic atypia with a typical mitotic count of