R3 정명화 /Prof. 장재영 Gastrointest. Endosc. 2012; 75:39-46

 Helicobacter pylori infection is closely related to the development of gastric cancer.  Prompted the WHO to categorize H pylori as a definite carcinogen for gastric cancer.  Animal experiments showed a preventive effect of H pylori eradication on gastric cancer.  A meta-analysis of 5 randomized interventional studies failed to demonstrate a significant reduction in the risk of gastric cancer after H pylori eradication

 Secondary metachronous gastric cancers develop because atrophic mucosa with a high risk of gastric cancer is mostly left untreated after endoscopic treatment.  Few studies showed H.pylori eradication a significant decrease in the incidence of metachronous gastric cancer after endoscopic resection of early gastric cancer during a 3 year follow up.  However, the average follow-up periods in these clinical studies were relatively short ( years).

 Duration: February 1998 and October 2009,  Multicenter,retrospective study  Kyushu University Hospital and at 6 other hospitals in the Fukuoka.  Eradication method: First : clarithromycin 200 mg, amoxicillin 750 mg a proton pump inhibitor twice daily for a week Second: metronidazole 250 mg/day instead of clarithromycin.  H.pylori detection: the rapid urease test, 13C urea breath test, histology  The background gastric mucosal atrophy at the time of endoscopic resection was assessed according to the Kimura- Takemoto classification.  Two observers independently reviewed all the endoscopic images at the time of endoscopic resection  Graded into 3 categories: mild (C-1 and C-2 types), moderate (C-3 and O-1 types), or severe (O-2 and O-3 types)

 Follow-up endoscopic examinations were conducted every 6 to 12 months after the initial endoscopic resection  Metachronous gastric cancer : new carcinoma developing in areas other than the site of primary gastric cancers at least 1 year after the endoscopic resection  It was confirmed by histological examination of specimens  H pylori infection was reevaluated after the diagnosis of metachronous gastric cancers by using the 13C urea breath test.

EGC Patient treated by EMR n=578 Investigation H.pylori n= 472 H.pylori negative n= 101 H.pylori positive n= 371

Persistent group (n =91) Eradiated group (n= 177) Metachronous gastric cancer >10yrs 13(14.3) 15 (8.5)P= Persistent group Eradiated group Metachronous gastric cancer <5 yrs 18.2% 5.3%P= 0.007

H pylori eradication in patients with endoscopic resection of early gastric cancer did not reduce the incidence of metachronous gastric cancer H pylori eradication should be performed before the progression of mucosal atrophy to prevent gastric cancer.