Telomere Length as a Prognostic Factor for Overall Survival in Colorectal Cancer Patients.

BACKGROUND/AIMS The stabilization of telomere length has important roles in the carcinogenesis of colorectal cancer. A systemic review and meta-analysis of published studies was performed to assess the prognostic role of telomere length in colorectal cancer. METHODS Pubmed and Embase were searched for eligible studies on the association between telomere length and overall survival in colorectal cancer patients. The pooled hazard ratio (HR) and corresponding 95% confidence intervals (95%CI) was calculated using fixed-effects or random-effects model according to the magnitude of between-study heterogeneity. RESULTS Seven individual studies with a total of 956 colorectal cancer patients were included. Long telomere length in cancer tissues was marginally associated with poorer overall survival (Random-effects HR = 1.85, 95% 0.90 to 3.83, P = 0.09). When using studies with adjusted estimates, long telomere length in cancer tissues was independently and significantly associated with poorer overall survival (Fixed-effects HR = 2.70, 95% 1.51 to 4.84, P = 0.001). However, short telomere length in peripheral blood leukocytes was independently and significantly associated with poorer overall survival (Fixed-effects HR = 2.01, 95% 1.46 to 2.77, P < 0.001). CONCLUSIONS There is some evidence for telomere length as a prognostic factor for overall survival in colorectal cancer patients. More studies with large number of participants are needed to further assess the prognostic significance of telomere length in colorectal cancer patients.