Methods Literature search strategy A computerized literature search on Cochrane Library, MEDLINE, EMBASE, CNKI (Chinese National Knowledge Infrastructure Database),

Wangfang (Database of Chinese Ministry of Science & Technology), and CBM (China Biological Medicine Database) was performed from the earliest possible find more date until July 30, 2012 (CNKI, Wangfang and CBM Database are the top three Chinese medical databases). The search terms included “gastric cancer” OR “gastric carcinoma” OR “carcinoma of stomach” OR “stomach neoplasms” AND “Cdx2” OR “caudal type homeobox 2”. The search was limited in studies in humans. Titles and abstracts of all citations were screened independently by two reviewers (Wang XT and Kong FB). We did not consider abstracts or unpublished reports. If more than 1 article was published by the same author using the same case series, we selected the study where the most individuals were investigated. Inclusion and

exclusion criteria To be eligible for this review, trials had to deal with gastric cancer only, to measure Cdx2 expression in the primary tumor (not in metastatic tissue or in tissue adjacent to the tumor), to evaluate correlation of Cdx2 expression and patients’ clinicopathological characteristics or 5-year survival rate, and to be published as a full paper in English or Chinese language literature. We reviewed abstracts of all citations and retrieved studies. For inclusion learn more in the meta-analysis, the identified articles have to provide information

on: (a) tumors verified by pathological examination; (b) methods used to determine Cdx2 expression and assign expression status by immunohistochemistry (IHC); (c) no preoperative radiotherapy and/or chemotherapy administered to the patients; (d) evaluation of the association between Cdx2 expression and prognostic Rebamipide factors of gastric cancer; (e) inclusion of sufficient data to allow the estimation of an relative risk (RR) with a 95% confidence interval (95% CI); (f) buy GSK690693 peer-reviewed and published original articles. Major reasons for exclusion of studies were: (a) Cdx2 expression was not evaluated by IHC; (b) no control; (c) duplicate; (d) no usable data reported; (e) cells or animals experiment; (f) letters to the editor, reviews, and articles published in a book. Data acquisition and quality assessment Samples were classified as positive if at least 5% of the tumor cells were stained in continuous scales or at least moderate staining in qualitative scales. The above cutoff was used by the majority of studies [11, 13–17]. When different definitions were used we contacted the primary investigators, and when data with this cutoff were not possible to retrieve we accepted the cutoff that was closest to this 5% cutoff level. In addition,there were two kinds of definition of the Cdx2 positive-expressed patients in IHC.