Primary midbrain germinoma.

Intracranial germinomas arising primarily in the midbrain are extremely rare and only one case has been reported in the literature. A 15-year-old boy presented with headache, diplopia, unsteadiness and personality changes. Brain MRI showed a heterogeneous lesion in the midbrain. The pineal body region was free. The preoperative diagnosis included brain-stem glioma, metastasis and lymphoma. Stereotactic biopsy was permitted in order to take a specimen and the diagnosis of germinoma was established. The patient responded well to chemotherapy and radiotherapy. Germinoma should be included in the differential diagnosis of midbrain lesions. Preoperative diagnosis is difficult and biopsy is still needed for such lesions.