Hidden puzzle in dysgenesis: a clinicopathological case report of unilateral gonadoblastoma in a dysgenetic Gonad

Abstract Background Gonadoblastoma is a rare in situ germ cell tumor composed of primitive germ cells admixed with sex cord–stromal elements, typically arising in dysgenetic gonads containing Y chromosome material. It is most commonly associated with disorders of sex development, particularly complete gonadal dysgenesis (Swyer syndrome). Case presentation We report an interesting case of 26-year-old phenotypic female who presented with primary amenorrhea and was found to have a 46,XY karyotype with bilateral dysgenetic gonads. CECT and MRI evaluation revealed a hypoplastic uterus with non-visualization of bilateral ovaries. Histopathological examination following a prophylactic bilateral gonadectomy demonstrated characteristic nests of germ cells and sex cord stromal elements with focal calcification and PAS-positive basement membrane material. Immunohistochemistry showed strong nuclear positivity for OCT3/4 in the germ cell component and cytoplasmic positivity for inhibin in the sex cord component, confirming the diagnosis of Gonadoblastoma. Conclusion This case highlights the importance of considering gonadal dysgenesis in patients presenting with primary amenorrhea and emphasizes the need for karyotype analysis in such cases. The identification of Y chromosome material warrants prophylactic bilateral gonadectomy because of the significant risk of Gonadoblastoma and invasive malignant germ cell tumors. Early surgical intervention with meticulous HPE after extensive sampling is mandatory for an accurate diagnosis which plays a crucial role in enhancing long term disease free survival and preventing adverse outcomes.