Suprasellar Mature Cystic Teratoma: A Case Report

Case Report: The authors report the case of a 57-year-old male patient who presented 7 weeks post resection of a skull base teratoma with vision changes, incontinence, ataxia, and altered mental status of 1 week’s duration. CT on presentation showed hydrocephalus unchanged from prior films. MRI before surgery revealed a large intrasellar mass that showed suprasellar extension, involvement of the ventricular system, and marked hydrocephalus with enlargement of the lateral and third ventricles. The patient underwent a pterional craniotomy/trans-sylvian approach for resection of suprasellar mass. Postoperative examination of the resected mass revealed a mature cystic teratoma.

Discussion: Intracranial germ cell tumors are rare and account for only 0.3 to 3.4% of all intracranial tumors. The prevalence is much higher in the earlier decades of life, with one peak in the neonatal and infancy period and another peak in children ages 5 through 14 years. Overall, these tumors appear to be more common in males, with a finding of 79.7% in males versus 20.3% in females reported in one paper. However, despite a clear preponderance of the more common pineal region tumors for male patients, suprasellar (neurohypophysis) region tumors may be more common in females. Although germ cell tumors are often mixed in type, five distinct types have been described in order of increasing malignant behavior: germinomas, teratomas, embryonal carcinomas, endodermal sinus tumors (yolk sac tumors), and choriocarcinomas. Specifically, teratomas are a type of germ cell tumor containing tissue elements of each of the three germ cell layers: endoderm, mesoderm, and ectoderm. They can be classified as mature, immature, or malignant. The majority of adult germ cell tumors are germinomas of the testes. Craniospinal axis teratomas are uncommon, and they have been discussed only in case reports and a rare case-series. Most intracranial germ cell tumors arise from midline structures, with the pineal gland being most common followed by the suprasellar compartment.

Conclusion: Intracranial germ cell tumors are rare and account for only 0.3 to 3.4% of all intracranial tumors. We report a rare case of a 57-year-old man who presented with symptoms related to obstructive hydrocephalus as a result of a large suprasellar mature cystic teratoma and rupture of the lesion with intraventricular extension of tumor content.