[Gonadoblastoma: Clinicopathological study and literature review of 3 cases]

To investigate the clinical feature, pathological morphology, special histopathological subtype and immunohistochemical characteristic of gonadoblastoma.

Three patients of gonadoblastoma treated from 2014 to 2020 were enrolled, and the clinical characteristics, histological morphology and immunophenotype were analyzed, and the literatures were also reviewed.

Three phenotypical females were 14,17 and 27 years old. Case 1 was 46,XX with normal gonadal development. Case 2 was 46,XY and case 3 was chromosomal chimeric type (46, XY 90%/45,X 10%), both with dysgenetic gonads. Microscopically, the morphology of classic type was observed in all cases more or less, manifesting small nests of primitive germ cells and surrounding clustered sex cord-like cells, usually with Call-Exner like bodies and calcification. In additon, the morphology of special subtype can be seen in case 1,exhibiting cord-like tumor cells, which was segmentated by cellular fibrous stroma. Cases 2 and 3 were accompanied by dysgerminoma components. Immunohistochemically,all the primal germ cells were positive for OCT3/4, PLAP and CDll7 , and sexcord-like cells were positive for inhibin, SF-1, SOX9 and FOXL2 . Patients were followed up for 10 years, 6 years and 4 years respectively without recurrence.

Gonadoblastoma is a rare germ cell-sex cord stromal tumor, which is usually accompanied by gonadal hypoplasia. As a special subtype, dissecting gonadoblastoma will be easily confused with dysgerminoma/seminoma, but the prognosis is better. So we should improve the understanding of this subtype and avoid overdiagnosis.