聴器扁平上皮癌における側頭骨病理組織所見

Temporal Bone Pathology in Squamous Cell Car-cinoma of the Ear

I．はじめに

　耳介，外耳道，側頭骨を侵す聴器癌のうち，耳介，外耳道に限局するものは比較的予後がよいが，中耳および乳突蜂巣へ進展したものでは予後が著しく不良である^1）。原発性聴器癌と転移性聴器癌が区別されるが，その発生頻度は一般に低く，過去の報告でも多数例の系統的報告は少ない。従って，本症の治療に関しては，未だ，十分な治療成績の評価に呈基づいた治療方法は確立されていない^2〜4）。

　病理学的には扁平上皮癌が最も多く^5,6），早期に鼓室および側頭骨へ侵入し，しばしば慢性中耳炎を合併して炎症巣内に陰蔽され，診断が遅れて予後不良になることが多い。

　The temporal bone in a case of squamous cell carcinoma, originating in the external auditory canal and extending into the middle ear and mastoid, was studied histopathologically.

　A 32-year-old male with the advanced cancer of T₃N₀M₀ was treated with the combination of Linac irradiation and radical operation of the middle ear, but lie died of pulmonary metastasis and purulent meningitis.

　The temporal bone findings revealed the extensive destruction of the external and middle ears with tumorous infiltration and osteoradionecrosis. The inner ear showed pictures of purulent labyrinthitis and severe atrophy of the membranous labyrinth due to irradiation. In spite of high dose of irradiation, the tumor mass remained in the internal auditory canal and pyramidal apical cells.

　From these, it is suggested that the control of squamous cell carcinoma, once extending into the middle ear and mastoid, is difficult with irradiation alone, and the subtotal resection of the temporal bone may be required for radical cure.