小脳橋角部の悪性類上皮腫の1例

Primary Intracranial Epidermoid Carcinoma Accompanied with Epidermoid Cyst in the Cerebellopontine Angle: A case report

I．はじめに

　類上皮腫（epidermoid cyst）は全脳腫瘍の約0.2-1％を占め^23），一般には全摘可能な良性腫瘍である．しかし，ときに悪性像を呈する報告も散見される．われわれは，第1回手術時には典型的な類上皮腫と診断されたにもかかわらず，その後徐々に症状が増悪し，7カ月後に行われた再手術で悪性類上皮腫（primary intracranialepidermoid carcinoma）と判明した1例を経験した．若干の考察を加え報告する．

A case of epidermoid carcinoma arising in an epider-moid cyst in the cerebellopontine angle is presented. Clinical features and CT appearance are discussed in comparison with those of benign epidermoid cyst.

A 43-year-old man was admitted to the Department of Neurosurgery, University of Tokyo Hospital on April 14, 1983, with complaints of right facial numbness and weakness of six months' history. On neurological examination, sensation of the right half of the face was decreased in all modalities. Marked atrophy of the ipsilateral temporal muscle was also noted. Right fa-cial paresis of peripheral type was evident.