Immunohistochemical staining of ovarian granulosa cell tumours with MIC2 antibody

Müllerian inhibiting substance, alpha-inhibin, and CD99 expression in sex cord-stromal tumors and endometrioid ovarian carcinomas resembling sex cord-stromal tumors

Müllerian inhibiting substance (MIS), alpha-inhibin, and CD99 are expressed by normal and neoplastic sex cord and stromal gonadal derivatives. The expression of MIS, inhibin, and CD99 was evaluated by immunohistochemistry in a series of 19 sex cord-stromal tumors and seven ovarian endometrioid carcinomas resembling sex cord-stromal tumors. Normal ovaries and testes from patients with the androgen insensitivity syndrome were used as control. All three markers were detected in primordial ovarian follicles and immature seminiferous tubules. Both inhibin and MIS were expressed by all sex cord-stromal tumors, but inhibin immunostaining appeared stronger and more diffusely distributed. CD99 was expressed by all adult and juvenile granulosa cell tumors, but only focally by Sertoli-Leydig cell tumors. In Sertoli-Leydig cell tumors, the three markers were predominantly expressed by the Sertoli cells. None of the seven endometrioid carcinomas with a sex cord-stromal pattern was positive for MIS or inhibin; two of them reacted for CD99, but their staining patterns were not membranous. Inhibin immunoreactivity was also detected in foci of stromal luteinization, occasionally present in these tumors. MIS, inhibin, and CD99 are potentially useful markers in the differential diagnosis between sex cord-stromal tumors and endometrioid carcinomas resembling sex cord-stromal tumors.

Precocious pseudopuberty due to a granulosa cell tumour in a seven-month-old female

We describe a juvenile granulosa cell tumour resulting in pseudopuberty in an infant female. The progression of the clinical signs of puberty were non-consonant and the diagnosis was complicated by marginally elevated serum alpha-fetoprotein levels. The histological appearance of the resected tumour and binding of MIC2 antibody to tumour cells confirmed the diagnosis.

Gynandroblastoma of the ovary: a case report with an immunohistochemical and ultrastructural study

An ovarian gynandroblastoma in a 60-year-old woman is described. The cut-surface of the right ovary showed multiple macrofollicles separated by white fibrous tissues and multiple ill-defined yellowish nodules. The tumour consisted of substantial amount of a granulosa cell element and a Sertoli cell element with intermingled Leydig cells. Immunohistochemically, the tumour cells in both the granulosa cell and Sertoli cell elements were positive for cytokeratin CAM5.2. The granulosa cell element showed strong membrane staining of Ewing's sarcoma antigen 013 and the Sertoli cell element was locally positive. Vimentin was observed in both the Sertoli cell element and the granulosa cells. Both elements and the Leydig cells were uniformly negative for epithelial membrane antigen, muscle specific actin, CD31 and CD34. The tumour was aneuploid by flow cytometry. The patient was well with no evidence of tumour five months after surgery.

Gynandroblastoma of ovary with juvenile granulosa cell component and heterologous intestinal type glands

An ovarian gynandroblastoma in a 15-year-old girl is described. The predominant component was juvenile granulosa cell tumour. Areas of adult granulosa cell tumour and Sertoli cell elements were also present. Stromal theca and luteinised cells were identified. An additional histological finding was the presence of heterologous intestinal type glands. There was positive immunohistochemical staining of juvenile and adult granulosa cell areas with inhibin and MIC2 antibodies. Electronmicroscopy showed a close ultrastructural resemblance between tumour cells in granulosa and Sertoli cell areas, in spite of differences in architectural pattern, suggesting that both morphological components may derive from a single cell of origin. The tumour demonstrates a unique combination of elements which has not previously been described.