Germinoma is a malignant germ cell tumor arising in the midline, largely in the pineal or suprasellar regions of the central nervous system, characterized by the presence of primitive, large, malignant germ cells and lymphocytes. Germinomas can often cause obstructive hydrocephalus presenting with severe headache, nausea, vomiting, papilledema, and changes in mental status. Other findings include ataxia, fatigue, weight loss, upward gaze paralysis, increased intracranial pressure, and vision loss. Germinomas occur in young patients between the ages of 10 and 20, with males affected more often than females.

Treatment includes surgical resection, radiation, and chemotherapy. Germinomas may reoccur after therapy.