More than 1000 Operations under Anesthesia were Performed in the Early and mid-19th Century in Japan

Background: In 1804, Japanese surgeon Seishu Hanaoka performed the world's first breast cancer surgery under general anesthesia, using the herbal extract, Mafutsusan, and continued to perform numerous operations thereafter. Although Seishu had many students, this method of anesthesia reportedly did not spread to the rest of Japan. Few studies have been made on the achievements of his students and the Hanaoka method performed in various areas of Japan. We therefore examined, through accessible literature, the extent of surgery performed in those days that employed Hanaoka-style general anesthesia.