Extensive 0-IIc (undifferentiated carcinoma) lesion around a gastric adenoma: a case report.

A 73-year-old woman underwent esophagogastroduodenoscopy (EGD) at a local hospital, which revealed a flat elevated lesion, approximately 15 mm in diameter, in the posterior wall of the lower gastric body. At our hospital, a repeat EGD and biopsy led to a diagnosis of moderately dysplastic adenoma. The patient requested endoscopic submucosal dissection (ESD).