A Primary Barrett's Adenocarcinoma with a Squamous Cell Carcinoma Component.

The present report describes an extremely rare case of Barrett's adenocarcinoma (BAC) with a squamous cell carcinoma (SCC) component. A 55-year-old man was diagnosed with esophageal adenocarcinoma on Barrett's esophagus. The patient underwent endoscopic submucosal dissection, but the pathology revealed deep submucosal invasive, moderately differentiated tubular adenocarcinoma and focal SCC with vascular invasion. In addition, morphological transition between adenocarcinoma and SCC components was confirmed. The patient underwent additional surgery, which revealed lymph node metastasis, and then received S-1 adjuvant chemotherapy. Based on the pathological findings, the transdifferentiation process may have a role in the histogenesis of this tumor.