title: Spontaneous regression of primary intracranial germinoma. A case report.
abstract: BACKGROUND
  Testicular seminomas are well known to regress spontaneously at a higher incidence than other tumors. To date, there have been no reports of spontaneous regression of an intracranial germinoma, although these tumors are histologically identical to testicular seminomas.
  
  
  METHODS
  The authors present a patient with a primary intracranial germinoma that regressed spontaneously.
  
  
  RESULTS
  A 21-year-old man was admitted to the study facility with acute onset of headache and vomiting. He had a 3-year history of polydipsia and polyuria. Computed tomography (CT) demonstrated a large tumor in the third ventricle, accompanied by hydrocephalus. He underwent ventriculoperitoneal shunt placement on the second day of hospitalization. A CT scan obtained on the fifth postoperative day demonstrated a remarkable decrease in tumor size. Because serial magnetic resonance imaging (MRI) demonstrated a gradual decrease in tumor size, tumor resection was not performed at that time. The patient was discharged and followed with MRI. The tumor continued to regress for more than 2 months. The patient was readmitted due to tumor regrowth, confirmed by MRI 4 months after the initial admission, despite the absence of symptom exacerbation. Two weeks later, the suprasellar portion of the tumor was resected through a right frontotemporal craniotomy. The histopathologic diagnosis was a germinoma. No concurrent tumors were found on whole body examination. The residual tumor gradually regressed after conventional radiation therapy and there has been neither tumor recurrence nor metastasis to date.
  
  
  CONCLUSIONS
  Although the precise cause of the transient partial regression is unknown, this case indicates that, like their testicular counterparts, intracranial germinomas may on occasion spontaneously regress.
authors.affiliation: Department of Neurosurgery, Tokyo Women's Medical College Dai-ni Hospital, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Ide
authors.forename: M
authors.initials: M
authors.lastname: Jimbo
authors.forename: M
authors.initials: M
authors.lastname: Yamamoto
authors.forename: S
authors.initials: S
authors.lastname: Hagiwara
authors.forename: M
authors.initials: M
authors.lastname: Aiba
authors.forename: O
authors.initials: O
authors.lastname: Kubo
mesh_terms: D000328:Adult; D002551:Cerebral Ventricle Neoplasms / Q000000981:diagnostic imaging / Q000601:surgery; D018237:Germinoma / Q000000981:diagnostic imaging / Q000601:surgery; D006801:Humans; D008297:Male; D009365:Neoplasm Regression, Spontaneous; D014057:Tomography, X-Ray Computed; D017287:Ventriculoperitoneal Shunt