Submucosal tumor-like early-stage mucinous gastric carcinoma: a case study.

Mucinous gastric carcinoma (MGC) is an unusual histologic subtype, and early detection of MGC is very rare. Early-stage MGC appears as an elevated lesion resembling a submucosal tumor (SMT) due to abundant mucin pools in the submucosa or mucosa. We report a rare case of SMT-like early-stage MGC. Tumor type was predicted preoperatively based on characteristic endoscopic findings, in which an SMT-like mass was observed at the gastric fundus. The tumor was covered by nearly normal mucosa, but with an opening allowing for the passage of copious mucus discharge. A total gastrectomy with Roux-en-Y esophagojejunostomy was subsequently performed. Histopathology of the tumor revealed early-stage (lamina propria) mucinous adenocarcinoma.