Many patients with gastric ulcers found on gastroscopy are worried about malignancy. This is because not only patients themselves are worried, but doctors often educate their patients this way, and doctors say this because that is what the textbooks say. The latest edition of Internal Medicine still includes gastric cancer as a major complication of gastric ulcers. This means that most people believe that gastric ulcers are likely to turn into gastric cancer, regardless of whether the percentage is large or small. As long as there is a slight possibility, one should not let go of this mouth. But in fact, the idea that gastric ulcers can transform into gastric cancer is one that has never been fully confirmed, and even one that has been questioned by various evidence. Checking the literature on the relationship between gastric ulcers and gastric cancer, it is generally believed that the earlier the gastric ulcer is, the more it can transform into gastric cancer. However, this conclusion is questionable when one considers that the diagnosis of gastric ulcer and gastric cancer used to rely heavily on barium meal examination. The diagnostic value of the barium meal is still held in high esteem in some of the early English-language gastroenterology monographs edited by the old guys, not knowing that the English monographs they refer to have been updated several editions ago and no longer use the barium meal as the main diagnostic tool for gastric disease. The gold standard for the diagnosis of gastric disease is gastroscopy plus biopsy pathology, which has been the consensus of gastroenterologists around the world. Although gastroscopy has since become available, the gastroscopy equipment of the 1960s and 1970s is incomparable to that of today, with thick tubes and hard mirrors, making it very painful for the patient. With such equipment, even the most dexterous and advanced physicians could not reach the level of primary care physicians today. With such a thing to do the examination of patients, miss diagnosis and misdiagnosis is not strange, not misdiagnosis and misdiagnosis is strange. Therefore, as early as the 1970s, some people suspected that the so-called gastric cancer transformed from gastric ulcer was actually a gastric cancer that was missed or misdiagnosed as gastric ulcer. When further studies were done, people who developed gastric cancer within two years after the first gastroscopy were excluded because they were more likely to be misdiagnosed. According to the law of tumor development, it takes several years for a non-cancerous lesion to develop into cancer, for example, it takes an average of 5-10 years for colon adenoma to develop into colon cancer. After excluding this group of patients, the incidence of gastric cancer in patients with gastric ulcer is greatly reduced. The debate over whether gastric ulcers can turn into gastric cancer has continued until now. After all, in the past, small cancerous foci were often seen in surgical specimens of gastric ulcers, which supported the potential of gastric ulcers to become gastric cancer. Unfortunately, now with the revolutionary advances in anti-ulcer drugs, gastric ulcer patients rarely need surgery anymore, so it can no longer be verified. Some animal experiments have also confirmed that after causing gastric ulcers, re-infusing mice with carcinogenic substances is more likely to induce gastric cancer. However, I am afraid that few people usually drink pure carcinogenic substances as drinks. Even if one could attribute all patients with gastric cancer found in gastric ulcers to missed diagnosis and misdiagnosis during the first gastroscopy and pathology examination, it makes no difference to the patients themselves. The patient’s concern can only be how likely he or she is to be diagnosed with gastric cancer in the future, whether it evolves or is misdiagnosed. If it is unlikely, there is no need to review the gastroscopy after treating the ulcer; if the possibility is considerable, then even after treating the ulcer, regular review of the gastroscopy is still needed. To answer this question, we need to clarify two points: firstly, how many benign gastric ulcers are misdiagnosed at present; secondly, whether the proportion of gastric cancer occurring in patients with benign gastric ulcers is higher than other lesions. Because we all know that gastric cancer can occur even in patients without gastric ulcer, and some lesions that are not gastric ulcer, such as atrophic gastritis and intestinal epithelial hyperplasia, also have a slightly higher rate of gastric cancer compared with normal gastric mucosa. If the proportion of gastric ulcer cancer is comparable to these lesions or even to normal people, then there is no need to review gastroscopy regularly. From the literature available in the abstract, it is true that follow-up of patients with gastric ulcers can detect many patients with early gastric cancer, and the five-year survival rate of patients with early cancer detected in such follow-up is much higher than that of patients with gastric cancer detected in the same period because of symptoms. From this perspective, regular gastroscopic review of gastric ulcer patients seems to be meaningful. But I am afraid that the significance lies more in the follow-up than because of gastric ulcers. If patients with atrophic gastritis, not gastric ulcer, are followed up for a long time, I am afraid that many patients with early gastric cancer can be detected. In practice, the literature in 1987 demonstrated that there was no significant difference in the detection rate of early gastric cancer between patients with and without ulcers in atrophic gastritis. Gastric ulcers do not seem to increase the risk of gastric cancer. Many subsequent studies have found that early gastric cancer is found in some patients with gastric ulcers, and some have further concluded that for every 50 patients with gastric ulcers given long-term follow-up, one case of early gastric cancer can be detected, but unfortunately these studies did not follow up other patients in the same period, so it is impossible to say whether the value is in follow-up or gastric ulcers. Rather, a number of studies have pointed out that if the gastroscopy and pathological biopsy at the time of the first gastroscopy are considered benign ulcers, there is little value in such a patient for a repeat gastroscopy. However, it is also noted that if either the gastroscopist or the pathologist suspects the presence of cancer, then a review must be performed. For the patient, if the gastroscopy, whether microscopic or pathological, concludes that the ulcer is benign, then there is no need to worry too much. Of course follow-up may be beneficial for everyone, and if someone insists on making a habit of regular follow-up gastroscopy, the doctor begs for it. If there is a slight suspicion, such as a combination of atypical hyperplasia, it is better to be careful.