Methods: A dataset composed of 11073 gastric cancers from 21 publications, combined with our cohort was included in the metaanalysis. We evaluated the association between the 5-year survival rate and the subtypes of gastric cancer based on histological grading or Lauren classification. All literatures were from Pubmed and Embase (up to December 2011).
Results: In our cohort from Shanghai Ruijin Hospital, the differentiated gastric cancer revealed a significantly higher accumulative 5-year survival rate, compared to that in poor-differentiated cases (62.6% vs 44.8%, P<0.001). Intestinal-type gastric cancer shown a higher accumulative 5-year survival rate, compared to that in diffuse-type cases (61.7% vs 41.1%, P<0.001). In overall meta-analysis, the poordifferentiated gastric cancer significantly increased the postoperative 5-year death risk, compared to the differentiated cases(OR=1.24, 95% CI 1.13-1.36, P＜0.001). The 5-year death risk was increased in the diffuse-type cases relative to the intestinal-type cases (OR=1.29, 95% CI 1.11-1.49, P＜0.001).
Conclusions: Gastric cancer with a differentiated histology or intestinal-type shows a better prognosis than individual with a poordifferentiated histology or a diffuse-type. Accurate histologic classification is desirable for gastric cancer handling.