早期食道基底細胞癌の1例

Early Basal Cell Carcinoma in the Esophagus, Report of a Case

要旨　食道基底細胞癌は非常にまれな疾患で，切除報告例は極めて少ない．最近，われわれは早期食道基底細胞癌の1切除例を経験した．患者は69歳の男性で，主訴は軽度の嚥下困難である．食道透視ではImからEiに長径約3cmの2～3個の小結節から成る境界不明瞭な腫瘤型病変を認めた．食道内視鏡では同部に表面にびらんを伴った褪色調の隆起性病変を認めた．生検組織診では低分化扁平上皮癌であった．右開胸食道亜全摘，R₃リンパ節郭清，後縦隔経路頸部食道胃管吻合術を施行した．摘出標本の病理組織学的検索では，皮膚の基底細胞に類似した小型の類円形細胞が増殖し，一見腺癌様の配列を示したが，真の腺腔形成はなく，食道基底細胞癌と診断した．

　The patient, a 69-year-old male, was admitted to our hospital with the complaint of slight dysphagia. Double contrast radiograph showed an ill-defined multi-nodular lesion with a diameter of 2 to 3 cm in the lower portion of the mid-esophagus. Esophagoscopy showed a discolored elevated lesion with a few erosions 35 cm below the incisors. Histologic examination of the biopsy specimens suggested poorly differentiated squamous cell carcinoma. A subtotal esophagectomy with right thoracotomy and reconstruction using stomach was performed. Histopathologic observation of the operated materials showed that numerous small cancer cells round or ovoid in shape had proliferated, forming a glandular structure. This glandular arrangement of tumor cells was actually only pseudo-glandular, as no mucin production was anywhere present and basement membrane had not been formed. The tumor cells had invaded no deeper than the submucosal layers. No metastatic regional lymph nodes were detected. These pathologic findings demonstrated that the tumor in this case was of basal cell origin, that is, basal cell carcinoma, adenomatoid type and in an early stage.

　As far as our review of the literature goes, there had been few reports on same resectable cases of basal cell carcinoma of the esophagus, and its clinical aspects and histogenesis was discussed in this report.