Guanghua Li1, Shuangjin Yu2, Jianbo Xu2, Xinhua Zhang2, Jinning Ye3, Zhao Wang4, Yulong He5. 1. Department of Gastrointestinal Surgery, First Affiliated Hospital of Sun-Yat-sen University, No. 58, Zhongshan 2nd street, 510080 Guangzhou, Guangdong, PR China. Electronic address: ligh26@mail.sysu.edu.cn. 2. Department of Gastrointestinal Surgery, First Affiliated Hospital of Sun-Yat-sen University, No. 58, Zhongshan 2nd street, 510080 Guangzhou, Guangdong, PR China. 3. Department of Gastrointestinal Surgery, First Affiliated Hospital of Sun-Yat-sen University, No. 58, Zhongshan 2nd street, 510080 Guangzhou, Guangdong, PR China. Electronic address: b2x33oh8@126.com. 4. Department of Gastrointestinal Surgery, First Affiliated Hospital of Sun-Yat-sen University, No. 58, Zhongshan 2nd street, 510080 Guangzhou, Guangdong, PR China. Electronic address: drzhaowang@163.com. 5. Department of Gastrointestinal Surgery, First Affiliated Hospital of Sun-Yat-sen University, No. 58, Zhongshan 2nd street, 510080 Guangzhou, Guangdong, PR China. Electronic address: lgh8711@126.com.
Abstract
BACKGROUND: The prognostic value of Helicobacter pylori (H. pylori) infection in gastric cancer patients has been investigated over many years; however, the results remain inconclusive. Thus, we performed a comprehensive review of currently available evidence via a systemic meta-analysis to evaluate the effects of H. pylori infection on the prognosis of gastric cancer patients. METHODS: Studies that evaluated the prognostic value of H. pylori infection in gastric cancer were extracted in March 2016 by searching PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials. We obtained or calculated hazard ratios (HRs) and the associated 95% confidence intervals (CIs) from the identified studies, and conducted random-effects model analyses of overall survival and progression-free survival. Twenty-four studies with a cumulative sample size of 7191 patients were included in our analysis. RESULTS: Our meta-analysis revealed that H. pylori infection is an indicator of improved overall survival in gastric cancer patients (HR, 0.79; 95% CI, 0.64-0.99); however, this was only true for European patients. The benefits of H. pylori infection were not detected in Asian gastric cancer patients (HR, 1.01; 95% CI, 0.91-1.12) or those in the United States (HR, 0.88; 95% CI, 0.73-1.05). Subgroup analyses revealed that the prognostic significance of H. pylori infection differed with respect to the year of study publication, number of patients, H. pylori detection method, tumor stage, H. pylori-positive rate, and risk of bias. The prognostic value of H. pylori infection on progression-free survival was unclear (HR, 0.84; 95% CI, 0.70-1.01). CONCLUSIONS: These data provide limited, moderate-quality evidence that H. pylori infection is an indicator of good prognosis in European gastric cancer patients. However, this is not necessarily true for other populations.
BACKGROUND: The prognostic value of Helicobacter pylori (H. pylori) infection in gastric cancerpatients has been investigated over many years; however, the results remain inconclusive. Thus, we performed a comprehensive review of currently available evidence via a systemic meta-analysis to evaluate the effects of H. pylori infection on the prognosis of gastric cancerpatients. METHODS: Studies that evaluated the prognostic value of H. pylori infection in gastric cancer were extracted in March 2016 by searching PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials. We obtained or calculated hazard ratios (HRs) and the associated 95% confidence intervals (CIs) from the identified studies, and conducted random-effects model analyses of overall survival and progression-free survival. Twenty-four studies with a cumulative sample size of 7191 patients were included in our analysis. RESULTS: Our meta-analysis revealed that H. pylori infection is an indicator of improved overall survival in gastric cancerpatients (HR, 0.79; 95% CI, 0.64-0.99); however, this was only true for European patients. The benefits of H. pylori infection were not detected in Asian gastric cancerpatients (HR, 1.01; 95% CI, 0.91-1.12) or those in the United States (HR, 0.88; 95% CI, 0.73-1.05). Subgroup analyses revealed that the prognostic significance of H. pylori infection differed with respect to the year of study publication, number of patients, H. pylori detection method, tumor stage, H. pylori-positive rate, and risk of bias. The prognostic value of H. pylori infection on progression-free survival was unclear (HR, 0.84; 95% CI, 0.70-1.01). CONCLUSIONS: These data provide limited, moderate-quality evidence that H. pylori infection is an indicator of good prognosis in European gastric cancerpatients. However, this is not necessarily true for other populations.