Germinoma with synchronous involvement of midline and off-midline structures associated with progressive hemiparesis and hemiatrophy in a young adult.

INTRODUCTION: Cerebral germinomas, the most common and least malignant intracranial germ cell tumors, usually arise in the pineal or suprasellar region and have characteristic clinical and radiological features. Germinomas more rarely occur in the thalamus, basal ganglia, and internal capsule, causing sometimes cerebral hemiatrophy and hemiparesis. More rarely, other clinical features can be fever of unknown origin, visual disturbance, and neuropsychiatric symptoms. Cerebral hemiatrophy can precede the imaging depiction of the off-midline mass. CASE: The authors present the first case of cerebral germinoma with synchronous involvement of the midline and off-midline structures, with unusual clinical and radiological presentation. DISCUSSION: The literature is reviewed, and the pathogenesis, the clinical findings, the imaging, and the therapy are discussed.