Diagnosis and treatment of a gastric hamartomatous inverted polyp: Report of a case

Gastric hamartomatous polyps are rare and difficult to diagnose. We report the case of a 43-year-old woman admitted to our hospital after an upper gastrointestinal series revealed a submucosal tumor. Upper gastrointestinal endoscopy showed a submucosal tumor (SMT), which was eroded with a depression on its surface, in the upper corpus. Endoscopic ultrasonography showed a heterogeneous tumor in the third layer. A laparoscopic wedge resection of the stomach allowed us to perform complete resection of the tumor, which measured 2.8 cm in diameter. The pathological diagnosis was a gastric hamartomatous inverted polyp. The postoperative course was uneventful. Only 27 cases of gastric hamartomatous polyps have been reported in Japan. Hamartomatous inverted polyps without a stalk are classified as the "SMT type" because the tumor is inverted into the submucosal layer, whereas polyps with a stalk are classified as the "polyp type." All of the polyps in past reports were resected endoscopically; however, laparoscopic wedge resection may be indicated for SMT-type hamartomatous inverted polyps larger than 2.0 cm in diameter.