Prognostic significance of β-catenin in colorectal cancer with liver metastasis

Aims: A decreased expression of beta-catenin has been known to be associated with tumour metastasis. The prognostic value of beta-catenin expression in colorectal cancer (CRC) patients with liver metastasis was evaluated. Materials and methods: Seventy patients who underwent curative resection for CRC with liver metastasis were included. Tissue samples from normal colon mucosa, primary CRC and metastatic liver lesions were prepared in tissue microarrays, and were stained by immunohistochemistry with beta-catenin antibody. The beta-catenin expression of primary CIRC tissues and metastatic liver tissues was analysed. Results: A high expression of beta-catenin (score > 6) was observed in 42.0% and 21.9% of primary colorectal tissues and metastatic liver tissues, respectively. The beta-catenin expression in metastatic liver tissues was significantly lower than in primary CRC tissues (P = 0.022). The patients were classified into two groups according to the difference in the beta-catenin expression score between the primary CRC and the liver metastasis. Group A was defined as patients showing a remarkably decreased expression of beta-catenin in their metastatic liver tissue and group B was defined as patients showing a maintained or increased beta-catenin expression in their metastatic liver tissue in comparison with their primary CRC. The overall survival and disease-free survival rates were better in group B than in group A, and this was statistically significant (P = 0.02, P = 0.002). Conclusion: The decreased expression of beta-catenin in a metastatic liver lesion may be a poor prognostic marker in CRC with liver metastasis and further investigation is necessary.