Pure Pineal Germinoma in a 17-Year-Old Adolescent: A Case Report and Literature Review

We report the case of a 17-year-old adolescent presenting with a large pineal region mass initially interpreted as a ruptured mature teratoma with intraventricular dissemination, complicated by triventricular hydrocephalus. Stereotactic biopsy enabled a definitive diagnosis of a pure germinoma, confirmed by its immunohistochemical profile (SALL4+, PLAP+, CD117+, CK−). The patient received three cycles of BEP chemotherapy (bleomycin, etoposide, cisplatin) followed by panventricular irradiation (24 Gy) with an additional tumor boost (16 Gy), resulting in good treatment tolerance and sustained radiologic stabilization. This case highlights the diagnostic challenges in distinguishing germinoma from teratoma on imaging, underscores the importance of stereotactic biopsy, and illustrates the effectiveness of combined chemoradiotherapy in intracranial germinomas.