Background Despite the large numbers of published documents analyzing the prognostic role of Ki-67 in NSCLC it is still not considered an established factor for routine use in clinical practice. results suggested that high Ki-67 expression was negatively associated with overall survival (OS; HR?=?1.59 95 CI Staurosporine 1.35-1.88 associated with a poorer overall survival (hazard ratio (HR) 1.56 95 confidence interval (CI) 1.30-1.87) it did not evaluate the association between Ki-67 expression and disease-free survival. Most importantly because of the limited number of studies and patients included it did not examine Staurosporine high Ki-67 expression in patients [2]. Thus a further meta-analysis investigation is needed to delineate the relationship between Ki-67 expression and prognostic significance in NSCLC more clearly. In this study we performed a meta-analysis to explore the relationship between Ki-67 expression and its prognostic value in NSCLC. Associations between Ki-67 expression and the clinicopathological features of NSCLC including age gender smoking status lymph node status and tumor differentiation were also evaluated. Methods The protocol Staurosporine including the objective of our analysis criteria for study inclusion/exclusion assessment of study quality primary outcome and statistical methods was in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (“PRISMA”) statement (Additional files 1 and 2) [10]. Study selection The PubMed Cochrane and Embase databases were searched systematically for relevant articles published up to November 1 2014 Search terms included Non-Small-Cell Lung Cancer (‘Carcinoma Non-Small-Cell Lung’ or ‘Carcinoma Non Small Cell Lung’ or ‘Carcinomas Non-Small-Cell Lung’ or ‘Lung Carcinoma Non-Small-Cell’ or ‘Lung Carcinomas Non-Small-Cell’ or ‘Non-Small-Cell Lung Carcinomas’ or ‘Carcinoma Non-Small Cell Lung’ or ‘Non-Small-Cell Lung Carcinoma’ or ‘Non Small Cell Lung Carcinoma’ or ‘NSCLC’) Ki-67 (‘Ki-67’ or ‘Ki67’ or ‘MIB-1’ or ‘MIB 1’ or ‘proliferative index’) prognosis survival and outcome in all possible combinations. Using these parameters we filtered out all the eligible articles and looked through their reference lists for additional studies. The systematic literature search was undertaken independently by two reviewers (SW and ZW) and ended in November 2014. Disagreements were decided through consensus with a third reviewer (CL). Authors of the eligible studies were contacted for additional data relevant to this meta-analysis as necessary. Inclusion and exclusion criteria Inclusion criteria for the primary studies were 1) addition of sufferers with a definite NSCLC medical diagnosis by pathology 2 dimension of Ki-67 appearance using immunohistochemistry (IHC) in principal NSCLC tissues 3 analysis of the partnership between Staurosporine Ki-67 appearance and general success (Operating-system) or disease-free success (DFS) in sufferers with NSCLC and option of valid success data either supplied directly or that might be computed indirectly and 4) publication in the British language. When writers had several magazines or reported on a single patient population just the newest or complete research was included. Exclusion requirements for the principal research had been 1) AURKB an overlap among articles or duplicate data; 2) the use of animals or cell lines; 3) insufficient data availability for estimating HR and 95?% CI such as common of abstracts editorials letters conferences data expert opinions reviews and case reports; 4) investigation of the relationship between Ki-67 and NSCLC using methods other than IHC; 5) inclusion of patients who underwent chemotherapy or radiotherapy interventions; and 6) a study sample comprising fewer than 20 patients. Data extraction and literature quality assessment Two investigators (SW and WZ) conducted the data extractions independently [10]. Any discrepancies were determined by critiquing the articles together until a consensus was reached. The following information was extracted from each article: name of first author and publication date; study population characteristics such as quantity of patients age group gender and treatment during follow-up; tumor data such as for example pathology kind of NSCLC Ki-67 appearance in the principal TNM and site stage; variables such as for example tissue Ki-67 dimension method cut-off worth for the Ki-67 level; success data such as for example DFS and OS; and relevant quality ratings. The principal data had been the HR and 95?% CI for success final results including DFS and Operating-system. For research quality control the Reporting was utilized by us Tips for Tumor Marker Prognostic.