The Development of Foveolar-type Gastric Adenocarcinoma during Maintenance Therapy of Vonoprazan for Reflux Esophagitis

We herein report the first case of foveolar-type gastric adenocarcinoma that developed after the initiation of vonoprazan (VPZ). A 51-year-old man had heartburn at the first visit and reflux esophagitis endoscopically, so he started taking VPZ. An approximately 5-mm-sized reddish polyp with a raspberry-like morphology was detected at the anterior wall of the upper body of the stomach 156 weeks after starting maintenance therapy with VPZ 10 mg/day. It was diagnosed as foveolar-type gastric adenocarcinoma based on a biopsy. Another approximately 4-mm-sized foveolar-type gastric adenocarcinoma was also detected at the posterior wall of the middle body of the stomach.

Automated summary

This case report highlights a rare case of foveolar-type gastric adenocarcinoma developing in a patient after the initiation of vonoprazan therapy. The presence of gastric adenocarcinoma on the basis of gastric polyps emphasizes the need to monitor for the development of gastric cancer on gastric polyps.