The Effect of Helicobacter pylori Eradication on Reducing the Incidence of Gastric Cancer

Abstract

Epidemiologically, the association between chronic Helicobacter pylori infection and development of gastric cancer is well established. Although the possibility of preventing gastric cancer by eradicating H. pylori infection was recently investigated by several research groups, the results remain controversial. The aim of this study was to determine whether the eradication of H. pylori infection would reduce the incidence of gastric cancer. In total, 304 patients with persistent H. pylori infection and 404 patients with H. pylori infection eradicated were examined annually for gastric cancer by endoscopy. Over an average of 3.1 years for the first group and 3.2 years for the second group, 13 and 6 patients, respectively, were diagnosed as having new gastric cancer. The cumulative incidence of gastric cancer was statistically different between the groups (P=0.019; log-rank test). The hazard ratio of H. pylori eradication was 0.335 by Cox proportional hazards model (P=0.047). Differentiated gastric cancer was found in 11 patients in the persistent infection group and 3 patients in the eradicated group. The incidence of differentiated cancer was significantly different (P=0.017) between the groups, but not for undifferentiated cancer (P=0.847). The results of the current study suggest that the eradication of H. pylori infection reduces the incidence of gastric cancer.

Gastric Cancers Emerging after H. pylori Eradication Arise Exclusively from Non-Acid-Secreting Areas

“…However, many of these included cases whose cancer lesions developed relatively soon after eradication, namely within 2 years after the treatment (Take et al 2005;Kamada et al 2005;Takenaka et al 2007;Fukase et al 2008;Ogura et al 2008).…”

“…There have been several reports that showed the incidence and characteristic features of gastric cancer after H. pylori eradication (Take et al 2005;Kamada et al 2005;Takenaka et al 2007;Fukase et al 2008;Ogura et al 2008;Yanaoka et al 2009;de Vries et al 2009). However, many of these included cases whose cancer lesions developed relatively soon after eradication, namely within 2 years after the treatment (Take et al 2005;Kamada et al 2005;Takenaka et al 2007;Fukase et al 2008;Ogura et al 2008).…”

“…Recent studies consistently reported that H. pylori eradication had some inhibitory effects on the subsequent development of gastric cancer, at least in certain conditions (Take et al 2005;Takenaka et al 2007;Fukase et al 2008;Ogura et al 2008). However, it also has been revealed that there are sporadic cases of gastric cancer even after successful eradication (Kamada et al 2005;Yanaoka et al 2009;de Vries et al 2009).…”

Preventive effects of etodolac, a selective cyclooxygenase‐2 inhibitor, on cancer development in extensive metaplastic gastritis, a Helicobacter pylori‐negative precancerous lesion

“…3 H. pylori eradication thus appears to be the most promising approach for the control of gastric cancer development, and the results of animal experiments have revealed that eradication of H. pylori, especially in the early stage, is effective for preventing stomach carcinogenesis. [4][5][6] However, current data indicate that H. pylori eradication does not lead to complete eradication of gastric cancer [7][8][9][10][11][12] and might be effective only in subjects without chronic atrophic gastritis (CAG) together with intestinal metaplasia. 7,10 Moreover, patients with extensive intestinal metaplasia-that is, metaplastic gastritis-should not be treated with eradication therapy, as bacterial load decreases with the progression of intestinal metaplasia, eventually resulting in spontaneous eradication.…”

Endoscopic Detection of Gastric Carcinoma After Helicobacter pylori Eradication: More Difficult or Just Hype?

“…Including the reports by Yamamoto et al [1] and Matsuo et al [2], [10 studies of GC detected after Hp eradication have been published to date [3][4][5][6][7][8][9][10]. The characteristics of post-eradication GC include: (a) detection *40 months after eradication; (b) lesions are histologically well differentiated; (c) gross lesion morphology is depressed; and (d) the lesions are small (10-20 mm diameter).…”