Helicobacter pyloriand Gastric Cancer: An Overrated Risk?

Cellular and molecular pathology of gastric carcinoma and precursor lesions: A critical review

“…However, the vast majority of people with H. pylori gastritis do not develop gastric cancer. Furthermore, the odds ratios for gastric cancer in H. pyloriinfected individuals do not differ widely between high-and low-risk countries [10]. The infection appears to affect older persons, and there is a general decline in the infection rate [11].…”

“…Prolonged H. pylori infection, resulting in an altered microenvironment in the stomach, together with other risk factors, allows colonization of other bacteria, particularly the anaerobes, and in-vivo production of procarcinogens in the stomach. In addition, H. pylori blocks gastric secretion of ascorbic acid, allowing the carcinogens to exert their damaging effect on the gastric epithelium [10]. It appears that in the late stage of carcinogenesis H. pylori per se is no longer essential.…”

Relationship between Helicobacter pylori, atrophic gastritis and gastric cancer

“…75 Crespi et al state that in Western countries such as the USA, the gastric cancer incidence has decreased despite a persistently high H. pylori prevalence of more than 50%. 74 As pointed out, however, in previous paragraphs, the prevalence of H. pylori, the prevalence of atrophic gastritis and intestinal metaplasia, and the incidence of gastric cancer have shown consistent decreases in the past few decades. 17,[76][77][78] This is consistent with similar trends both in Europe and the USA in the incidence of peptic ulcer disease, another condition strongly related to H. pylori infection.…”

“…39,[81][82][83] A second criticism is that the prevalence of H. pylori is the same among men and women, whereas the incidence of gastric cancer is higher among men. 74 In reply, there is first of all some evidence that the prevalence of H. pylori may actually be higher among men than among women, which might account for part of the observed differences in gastric cancer incidence. 84 In addition, All three scenarios are based on inexact figures and therefore yield inexact, rough estimates.…”

“…72 These conclusions have been strongly criticized as being unjustified and non-scientific. 74 These comments are based on a number of important and partly unresolved issues. 75 Crespi et al state that in Western countries such as the USA, the gastric cancer incidence has decreased despite a persistently high H. pylori prevalence of more than 50%.…”