Well differentiated cerebellar tissue within a mature cystic teratoma.

We describe the case of a 27 year-old woman presenting with acute abdominal pain due to torsion of a right ovarian cyst. Histopathological examination of the excised lesion revealed a mature cystic ovarian teratoma consisting primarily of a highly organized cerebellar component, an exceedingly rare finding. The possibility of a malignant neuroepithelial tumor arising from immature precursor cells within this neural tissue justifies complete excision of such lesions.