前頭洞・側頭窩へ進展した涙腺悪性多形腺腫の1症例—18年の経過で悪性化した症例について

A Lacrimal Gland Tumor with Malignant Change in 18 Years-Report of a Case

　はじめに

　涙腺には耳下腺と同様に多形腺腫が好発するが，再発性耳下腺腫瘍の悪性化と同様に，涙腺多形腺腫の再発例にも悪性化の報告がある。われわれは初回手術から18年の経過で悪性化した涙腺腫瘍の1症例を経験したが，現在まで最終手術後7年の経過観察を行い経過は順調である。症例の画像所見および進展経路について，文献的考察とともに報告する。

A 60-year-old man underwent three operations for a left lacrimal gland tumor. Histopathological diagnosis of the tumor at the first operation was benign pleomorphic adenoma. Recurrence occur-red after 16 years and CT showed a well circum-scribed soft tissue density mass at the left lacrimal gland fossa. At the second operation the tumor was adherent to the upper lateral region of the left orbit and 10 the upper rim, and the lateral orbital wall was partially destroyed by the tumor.

Clinical impression was a malignant change of pleomorphic adenoma, but histological report was again benign pleomorphic adenoma. It only took one month before the second recurrence.

Plain X-P and CT showed the invasion of the tumor to the frontal sinus and the temporal fossa. Histopathological diagnosis was malignant pleo-morphic adenoma at the third operation. The patient received radiotherapy of 60 Gy. After 7 years of the third operation the clinical course has been uneventful.