Dr. Toyoshima is an expert in the field of Gastroenterology, especially of H. pylori diagnosis, of gastric cancer after H. pylori eradication, and of quality indicators of colonoscopy such as colorectal polyp detection. Dr. Toyoshima is a director of Toyoshima Endoscopy Clinic, out-patient clinic specialized for screening endoscopy. Toyoshima Clinic performed 10,000 endoscopy annually. The adenoma detection rate of the clinic is about 50% which shows the high-quality clinical practice.