Germinoma in late adulthood with extensive dissemination: a case report and literature review

Central nervous system germ cell tumors (CNS GCTs) are exceptionally rare in patients aged 60 years or older. We report a 61-year-old man with progressive weight loss and endocrine dysfunction over 20 months, in whom magnetic resonance imaging revealed enhancing lesions including the suprasellar and sellar regions, optic tracts, ventricular walls, corpus callosum, and dorsal medulla. Biopsy findings supported a diagnosis of germinoma in the sampled tissue, and DNA methylation profiling demonstrated a molecular profile consistent with conventional germinoma. The patient underwent whole ventricular irradiation and carboplatin-etoposide chemotherapy. Febrile neutropenia during the first cycle required subsequent etoposide dose reductions, but he achieved marked radiographic regression. A descriptive review identified five cases, including the present case, for which sufficient individual clinicopathological information was available. This case highlights that CNS GCTs in older adults may radiologically mimic primary CNS lymphoma and that integrated pathological assessment, including morphology and immunohistochemistry, is essential for diagnosis. In this diagnostically challenging presentation, DNA methylation profiling provided complementary molecular support for the histopathological diagnosis of conventional germinoma.