早期食道類基底細胞癌の1例

Basaloid-Squamous Cell Carcinoma of the Esophagus, Report of a Case

要旨　患者は85歳，女性．咽頭部違和感を主訴に内視鏡検査が行われた．上切歯列より25cmの部に約2cm大の隆起性病変を認めた．隆起の大部分は上皮に覆われているが，その頂に数個のなだらかな小結節状隆起を有し，中央にはびらんを認めた．生検にて扁平上皮癌の診断を受け手術を行った．1.3×1.1cm，0-I sepの病変であった．組織学的検査では癌細胞は全体に基底細胞に類似し，充実性に発育していた．癌胞巣は粘膜固有層で増殖して上皮を上方へ圧排し，隆起の中央部で癌の露出が見られた．n₀で一部粘膜下層に浸潤した早期の類基底細胞癌と診断した．本例の内視鏡所見は上皮下で増殖する類基底細胞癌の特徴をよく示していた．

　An 85-year-old woman with a complaint of discomfort of pharynx was admitted to our hospital. Upper GI x-ray examination showed a small protruding lesion in the middle third of the thoracic esophagus (Fig. 1a, b). Endoscopic examination revealed a protruding tumor, approximately 2 cm in size, covered with grossly normal epithelium at 25 cm distal from the incisors (Fig. 2a, b). Erosion was noted on the top of the lesion. Biopsy specimens showed squamous cell carcinoma and operation was performed (Fig. 3). Histological examination revealed solid proliferation of basaloid cells which contained scanty cytoplasm and hyperchromatic nuclei (Fig. 4a, b). The tumor was mostly located in the lamina propria and push normal mucosa upward. Macroscopic appearance of the lesion was consistent with its histological findings. No lymph node metastasis was noted. The diagnosis of this patient was basaloidsquamous cell carcinoma of the esophagus.