It is generally believed that the cancer rate of GERD is very low. However, it should be noted that a few cases of reflux esophagitis, which are not regularly treated or not treated, may cause long-term erosion of the mucosa of the lower esophagus by the refluxed material, which may lead to “columnar epithelial metaplasia” that should not occur, and then there is a risk of cancer. Long-term irritation of the esophageal mucosa by gastric contents will cause changes in the mucosa, i.e., precancerous lesions, such as atypical hyperplasia, which will lead to tumors, such as adenocarcinoma of the lower esophagus and pancreatic cancer. In the process of esophageal mucosa repair, squamous epithelium is replaced by columnar epithelium called “Barrett’s esophagus”, which is the main precancerous lesion of esophageal adenocarcinoma. The incidence of pancreatic cancer in China is high, and it is thought to be related to the long-term stimulation of GERD. If Barrett’s esophagus is accompanied by atypical hyperplasia, long-term untreated may increase the chance of cancer. the estimated risk of esophageal cancer in patients with Barrett’s esophagus is about 1%. However, recent epidemiologic data suggest that the histologic type of Barrett’s esophagus is particularly important, and that only intestinal-type metaplasia (marked by the presence of cupped cells) progresses to cancer. The definitive diagnosis of Barrett’s esophagus and the identification of its histological type and the determination of atypical hyperplasia and adenocarcinoma must be made by endoscopy and biopsy. Atypical hyperplasia is diagnosed histologically and can be classified as low or high grade. Patients with Barrett’s esophagus with high grade atypical hyperplasia have a significantly increased risk of developing cancer. The development of cancer in Barrett’s esophagus is thought to begin with gastroesophageal reflux. One study showed that patients with GERD who had heartburn, reflux, or two or more symptoms more than once a week had a 7.7-fold increased risk of developing esophageal adenocarcinoma. This study also showed a 43.5-fold increase in the risk of esophageal adenocarcinoma in patients with increased severity and frequency of symptoms and a disease duration of more than 20 years. These data add to the concern about the risk of cancer in GERD, which is a major cause of esophageal adenocarcinoma, and the risk of cancer increases with the duration of GERD symptoms. Gastroesophageal reflux should be considered as a potential cause for the development of carcinoma, and patients should be treated aggressively as early as possible in order to prevent serious clinical consequences. The cancer rate of GERD is generally considered to be low. However, it should be noted that in a few cases of GERD, the mucous membrane of the lower esophagus is eroded by the refluxed material for a long time due to the lack of regular treatment or untreated, and “columnar epithelial metaplasia” which should not occur may occur, and then there is a risk of carcinogenesis. Long-term irritation of the esophageal mucosa by gastric contents will cause changes in the mucosa, i.e., precancerous lesions, such as atypical hyperplasia, which will lead to tumors, such as adenocarcinoma of the lower esophagus and pancreatic cancer. In the process of esophageal mucosa repair, squamous epithelium is replaced by columnar epithelium called “Barrett’s esophagus”, which is the main precancerous lesion of esophageal adenocarcinoma. The incidence of pancreatic cancer in China is high, and it is thought to be related to the long-term stimulation of GERD. If Barrett’s esophagus is accompanied by atypical hyperplasia, long-term untreated may increase the chance of cancer. the estimated risk of esophageal cancer in patients with Barrett’s esophagus is about 1%. However, recent epidemiologic data suggest that the histologic type of Barrett’s esophagus is particularly important, and that only intestinal-type metaplasia (marked by the presence of cupped cells) progresses to cancer. The definitive diagnosis of Barrett’s esophagus and the identification of its histological type and the determination of atypical hyperplasia and adenocarcinoma must be made by endoscopy and biopsy. Atypical hyperplasia is diagnosed histologically and can be classified as low or high grade. Patients with Barrett’s esophagus with high grade atypical hyperplasia have a significantly increased risk of developing cancer. The development of cancer in Barrett’s esophagus is thought to begin with gastroesophageal reflux. One study showed that patients with GERD who had heartburn, reflux, or two or more symptoms more than once a week had a 7.7-fold increased risk of developing esophageal adenocarcinoma. This study also showed a 43.5-fold increase in the risk of esophageal adenocarcinoma in patients with increased severity and frequency of symptoms and a disease duration of more than 20 years. These data add to the concern about the risk of cancer in GERD, which is a major cause of esophageal adenocarcinoma, and the risk of cancer increases with the duration of GERD symptoms. GERD should be considered as a potential cause for the development of cancer and patients should be treated aggressively as early as possible in order to prevent serious clinical consequences.