[Spontaneous regression of primary intracranial germinoma: a case report].

: Here we report a case in which an intracranial germinoma displayed spontaneous regression. An 11-year-old boy presented with polyuria and headache. Computed tomography (CT) and magnetic resonance imaging (MRI) revealed tumors in the suprasellar and pineal regions, and obstructive hydrocephalus. As repeat MRI demonstrated shrinkage of these tumors, resection was deferred. The patient was discharged and followed up with serial MRI. The tumor continued to regress for three weeks; however, the patient was readmitted due to tumor regrowth. We performed endoscopic biopsy, and histopathologic diagnosis was germinoma. The patient underwent three courses of combined chemotherapy and radiotherapy, and complete response was achieved. Although the precise cause of the transient regression is unknown, racranial germinoma may occasionally unde rgo spontane ous regression.