The incidence rate of gastric cancer in Japan is high. Early screening and treatment are promoted. As early as 1950s, the mortality rate of gastric cancer in Japan ranks the top of the malignant tumor. Japan has gradually realized the importance of early screening and early treatment for gastric cancer to reduce the mortality rate of gastric cancer, and has begun to explore the related issues.
In the mid-term of 1950s, Nagano Prefecture and Miyagi Prefecture took the lead in applying X-ray barium meal examination to gastric cancer screening, and gradually extended it to Japan.
With the strong support of national policies, 400000 people underwent gastric cancer screening in Japan in 1964, and this number was expanded to 4 million in 1970. But at that time, gastric cancer of Japan screening policy moved forward in controversy.
Under this historical background, Japanese scholars have made unremitting exploration in the treatment of early gastric cancer. In 1974, endoscopic polypectomy was first used in Japan to treat pedicled or sub pedicled early gastric cancer.
In 1984, the true polyp EMR of endoscopic appeared. The treatment method of this technology is relatively simple. It can judge whether the endoscopic resection is complete through the complete histological diagnosis of the resected specimens. It has gradually been widely accepted in Japan and is regarded as an endoscopic treatment strategy for early gastric cancer with small lesions.
In 1988, endoscopic resection technique (ERHSE) with local injection of hypertonic adrenaline normal saline appeared. In this technique, hypertonic saline and diluted epinephrine are injected locally into the lesion, and then the periphery of the lesion is cut with a needle knife, and then removed with a snare.
This technology can be applied to larger lesions to achieve more complete resection, but it has higher requirements for EMR equipment, it requires the use of needle knife, and the risk of perforation will also increase.
In 1992, polyp EMR assisted by transparent cap appeared. A transparent cap was placed in front of the lens. Different sizes of transparent cap can be selected according to the diameter of endoscope and the size of lesion.
After submucosal injection of the lesion, a special crescent shaped snare is placed in the groove at the top of the transparent cap. After suction, the lesion enters the transparent cap and is sleeved and tightened by the snare. It is used for the resection of early esophageal cancer and gradually for the resection of early gastric cancer.
In order to solve the endoscopic resection of early gastric cancer with large lesions, the National Cancer Center Hospital (NCCH) of Japan first used the improved needle knife for endoscopic resection under direct vision of submucosa in the 1990s. This technology is called ESD equipment resection (under direct vision of submucosa).