The diagnosis and management of mixed intracranial germ cell tumors may be complicated by the diversity present within this tumor category. Mixed germ cell tumors demonstrate variable natural histories which may be altered by the inclusion of even the most minute immature histological components. We report the case of an 18-year-old male who presented with a 3-month history of progressive headache and nausea leading to lethargy. Imaging revealed a giant pineal region mass extending superiorly from the roof of the fourth ventricle into the lateral ventricle, with resultant obstructive hydrocephalus. No spinal lesions were noted. Following gross total resection, the patient experienced marked improvement. Pathologic analysis identified an uncommon tumor composition: mature teratoma (96%), immature teratoma (2%), and germinoma (2%). Guided by the immature component, chemotherapy and radiation were added post-operatively to provide this patient with the greatest chance of long-term survival. Intracranial pathology, including germ cell tumors, should be included in the differential for any young patient presenting with new and progressive headache and nausea. This case emphasizes the benefit of a multimodal approach to mixed germ cell tumors of the pineal region and the importance of careful pathologic review of all submitted material.

1. Kyritsis, AP. Management of primary intracranial germ cell tumors. J Neurooncol 2010; 96: 143–149.
Google Scholar | Crossref | Medline2. Hirato, J, Nakazato, Y. Pathology of pineal region tumors. J Neurooncol 2001; 54: 239–249.
Google Scholar | Crossref | Medline | ISI3. Gittleman, H, Cioffi, G, Vecchione-Koval, T, et al. Descriptive epidemiology of germ cell tumors of the central nervous system diagnosed in the United States from 2006 to 2015. J Neurooncol 2019; 143: 251–260.
Google Scholar | Crossref | Medline4. Vasiljevic, A, Szathmari, A, Champier, J, et al. Histopathology of pineal germ cell tumors. Neurochirurgie 2015; 61: 130–137.
Google Scholar | Crossref | Medline5. Gao, Y, Jiang, J, Liu, Q. Clinicopathological and immunohistochemical features of primary central nervous system germ cell tumors: a 24-years experience. Int J Clin Exp Pathol 2014; 7: 6965–6972.
Google Scholar | Medline6. Matsutani, M, Sano, K, Takakura, K, et al. Primary intracranial germ cell tumors: a clinical analysis of 153 histologically verified cases. J Neurosurg 1997; 86: 446–455.
Google Scholar | Crossref | Medline | ISI7. Sawamura, Y. Current diagnosis and treatment of central nervous system germ cell tumours. Curr Opin Neurol 1996; 9: 419–423.
Google Scholar | Crossref | Medline8. Fetcko, K, Dey, M. Primary central nervous system germ cell tumors: a review and update. Med Res Arch 2018; 6: 1719.
Google Scholar | Medline9. Murray, MJ, Bartels, U, Nishikawa, R, et al. Consensus on the management of intracranial germ-cell tumours. Lancet Oncol 2015; 16: e470–e477.
Google Scholar | Crossref | Medline10. Bruce, JN, Stein, BM. Surgical management of pineal region tumors. Acta Neurochir (Wien) 1995; 134: 130–135.
Google Scholar | Crossref | Medline11. Demir, MK, Yapicier, O, Karakaya, OF, et al. A primary third ventricle mixed germ cell tumor with leptomeningeal dissemination of immature teratoma component. Childs Nerv Syst 2019; 36: 629–633.
Google Scholar | Crossref | Medline12. Ogawa, K, Toita, T, Nakamura, K, et al. Treatment and prognosis of patients with intracranial nongerminomatous malignant germ cell tumors: a multiinstitutional retrospective analysis of 41 patients. Cancer 2003; 98: 369–376.
Google Scholar | Crossref | Medline | ISI