AIM: To investigate the changing pattern of β-catenin expression and its prognostic value in advanced colorectal cancer (CRC).METHODS.Archival tumor samples were analyzed for β-catenin using immunohistochemisry (IHC) in 95 patients with advanced CRC.RESULTS: Membranous β-catenin expression was found in the normal colorectal epithelium.Almost 100% of CRCcases showed membranous and cytoplasmic expression,and 55 (58%) cases showed nuclear expression.In univariate (Kaplan-Meier)survival analysis,only the nuclear index (NI) was a significant predictor of disease free survival (DFS) (P=0.023; n = 35),with a NI above the median associated with longer DFS (34.2 mo) than those with a NI below the median (15.5 mo) (P = 0.045,ANOVA).The other indices were not significant predictors of DFS,and none of the three tested indices (for membranous,cytoplasmic,or nuclear expression) predicted diseasespecific survival (DSS).However,when dichotomized as positive or negative nuclear expression,the former was a significant predictor of more favorable DFS (P =0.041) and DSS (P = 0.046).CONCLUSION: Nuclear β-catenin expression provides additional information in predicting patient outcome in advanced CRC.