[Germ cell tumor in the basal ganglia with elevated serum and CSF alpha-fetoprotein levels]

Intracranial germ cell tumors usually locate either in the pineal region or in the suprasellar region or both. Primary occurrence of germ cell tumor in the basal ganglia is rare. To our knowledge, only 17 cases have been reported in the literatures, and all the patients were Japanese. None of these patients presented elevated serum and CSF AFP levels in the literatures. We are reporting a patient with a germ cell tumor which developed in the left basal ganglia and showed high serum and CSF alpha-fetoprotein (AFP) levels. The patient was a 12-year-old boy who had been completely well until five months prior to the first admission when he developed weakness of right extremities. On admission he showed a right hemiparesis of mild degree and right hypesthesia. CT-scans demonstrated a homogeneous high density area over the caudate head and the putamen on the left side. The anterior limb of the left internal capsule and a part of the posterior limb were also involved. The lesion was moderately enhanced by the contrast medium. Stereotaxic biopsy of the lesion was uncontributory and he was discharged for follow up. Five months later, CT-scans demonstrated the enlargement of the high density area with perifocal edema. Then we performed a craniotomy, and the tumor which was soft and dark red in colour was biopsied at the wall of the anterior horn of the left lateral ventricle. Histopathology of the specimen showed germinoma of two-cell pattern.(ABSTRACT TRUNCATED AT 250 WORDS)