Helicobacter pylori (H. pylori) is associated with gastric cancer in epidemiological studies.Gastric atrophy and intestinal metaplasia caused by H. pylori are considered as precancerous lesions, but whether H. pylori eradication improves these lesions is controversial.The primary objective of this study is to evaluate whether Helicobacter pylori eradication improves glandular atrophy and intestinal metaplasia which are known to be precancerous condition in patients undergoing subtotal gastrectomy for gastric cancer.

Helicobacter pylori (H. pylori) is a primary etiological agent leading to chronic gastritis and peptic ulcer. The organism is also associated with gastric cancer in epidemiological studies. However, detailed mechanism of carcinogenesis remains unknown. Histolopathological studies indicate that chronic H. pylori infection progresses over decades through stages of chronic gastritis, atrophy, intestinal metaplasia, dysplasia and cancer. Gastric atrophy and intestinal metaplasia are considered as precancerous lesions, but whether H. pylori eradication improves these lesions is controversial. And the issue has not been evaluated in gastric cancer patients. However, despite the lack of evidence proven by a well-designed study, current guidelines from Europe and Japan recommend H. pylori eradication treatment in patients who were treated for gastric cancer by surgically or endoscopically. Thus, it is important to evaluate whether H. pylori eradication can improve known precancerous lesion, i.e. glandular atrophy and intestinal metaplasia in gastric cancer patients. Such histological improvement may eventually reduce secondary gastric cancer development and provide evidence for current guidelines. Helicobacter pylori is a primary etiological agent leading to chronic gastritis and peptic ulcer. The organism is also associated with gastric cancer in epidemiological studies. However, detailed mechanism of carcinogenesis remains unknown. Histolopathological studies indicate that chronic H. pylori infection progresses over decades through stages of chronic gastritis, atrophy, intestinal metaplasia, dysplasia and cancer. Gastric atrophy and intestinal metaplasia are considered as precancerous lesions, but whether H. pylori eradication improves these lesions is controversial. And the issue has not been evaluated in gastric cancer patients. However, despite the lack of evidence proven by a well-designed study, current guidelines from Europe and Japan recommend H. pylori eradication treatment in patients who were treated for gastric cancer by surgically or endoscopically. Thus, it is important to evaluate whether H. pylori eradication can improve known precancerous lesion, i.e. glandular atrophy and intestinal metaplasia in gastric cancer patients. Such histological improvement may eventually reduce secondary gastric cancer development and provide evidence for current guidelines.

Inclusion Criteria:

• AGC or EGC confirmed by endoscopy
• Histologically confirmed adenocarcinoma of stomach
• Helicobacter pylori infection was confirmed by biopsy and CLO
• Pre op CT stage: IA, IB, II, IIIA according to UICC TNM classification system
• Pre op biopsy (body LC side) shows either intestinal metaplasia or glandular atrophy (at least grade 1)
• Tumor location is suitable for subtotal gastrectomy- i.e. at or distal to lower body
• Informed consent should be signed

Exclusion Criteria:

• Recurrent gastric cancer
• Previous serious side effect to antibiotics
• H. pylori eradication treatment history
• Other malignancy within the past 5 years
• Pregnant or nursing women
• Serious concurrent infection or nonmalignant disease such as liver cirrhosis, renal failure, cardiovascular diseases
• Psychiatric disorder that would preclude compliance