Budding invasive margin and prognosis in colorectal cancer – no direct association with β-catenin expression

Cancer cell budding at the invasive margin has been associated with poor prognosis in rectal cancer. β-Catenin is an adhesion protein involved in the nuclear Wnt/β-catenin pathway, and mesenchymal transition of colorectal cancer cells. Hence, we investigated the relationship between cancer cell budding at the invasive margin, β-catenin expression, and 5-year-survival in colorectal cancer. Four hundred and sixty six colorectal cancer specimens were analysed for budding margin, and 108 specimens from the same set for β-catenin by immunohistochemistry. A budding margin was present in 24.0% of the cases and predicted a poor 5-year-survival (15.4%, P < 0.00001). Nuclear β-catenin expression increased from the central area towards the invasive margin (P < 0.001), but did not predict budding. Budding margin is an independent factor associated with poor prognosis in colorectal cancer, and could be utilised in diagnostic pathology. Nuclear β-catenin was often found at the invasive margin, but is unlikely to be the sole cause of budding.