Resection of a Submucosal Tumor-Like Superficial Carcinoma in Middle Thoracic Esophagus Concomitant with Mucosal Adenocarcinoma and Submucosal Squamous Cell Carcinoma: A Case Report and Review of Literature.

A 67-year-old man was pointed out mucosal irregularity on health check-up and was referred to our institution. Diagnostic examinations were performed and an aggregated type 0-IIa lesion having 3 small protrusions was recognized in the middle thoracic esophagus. Endoscopic biopsy led to diagnosis of esophageal cancer concomitant with adenocarcinoma and squamous cell carcinoma. Thoracic esophagectomy with 3-fields lymph node dissection was performed via a right thoracoabdominal approach and reconstructed with stomach roll. Three submucosal tumors like small protrusions were recognized in resected specimen. One of them was well differentiated tubular adenocarcinoma which occupied in mucosal layer. The other two were moderately differentiated squamous cell carcinoma. They existed very near but no connection was recognized by serial section. The adenocarcinoma existing in middle esophagus is very rare. Almost all of them were submucosal or advanced cancers. When we searched with the ICHUSHI database (a domestic medical literature database service provided by the NPO Japan Medical Abstracts Society) and the PubMed database, there was no report of mucosal adenocarcinoma occurred in middle thoracic esophagus in the past 10 years. Then this report was thought to be the first report of mucosal adenocarcinoma in middle thoracic esophagus in the world.