後頭部皮下に巨大腫瘤を形成した類上皮腫の1例

A Case of a Giant Epidermoid Cyst on the Occipital Scalp

I．はじめに

　頭部の腫瘤性病変は，日常診療においてしばしば遭遇され，外来にて治療されていることが多い．しかし，腫瘤の大きさや性状によっては鑑別診断が必要な症例も存在する．

　今回，われわれは長年の経過のうちに増大してきた，成人の後頭部皮下に巨大腫瘤を形成した類上皮腫の1例を経験したので，鑑別診断を含めて文献的考察を加えて報告する．

The authors report a case of a 61-year-old woman presenting with a giant mass on the occipital scalp. The patient had no neurological deficits and was of normal in-telligence. The lesion was soft and covered by an unre-markable epidermis. The preoperative radiologic evalua-tion was made by CT, MR Imaging, and by cerebral angi ogram. The mass produced an inhomogeneously low-intensity signal involving also a high-intensity signal. It was shown, on the T1 weighted image, that it did not communicate with the intracranial space, and there was no gadolinium-enhanced lesion. MR Imaging was supe-rior to CT in the evaluation of the giant mass on the scalp and was particularly useful in surgical planning. At sur-gical resection, a soft fluffy, white-colored tumor which measured 16×10×7cm was totally removed. Patholo-gical diagnosis of the tumor was epidermoid cyst.