Protein markers in colorectal cancer - Predictors of liver metastasis

Objective To assess the significance of the expression of five protein markers (nm23, p53, c-erbB-2, u-PA, and VEGF) to the development of metastasis in colorec tal cancer. Summary Background Data The metastatic cascade is a complex multistep process involving several gen etic alterations, angiogenesis activation, and tissue proteolysis. Although the prognosis of colorectal cancer depends on the stage of the tumor, the development of metastasis is difficult to predict. Methods Paraffin-embedded specimens of 58 patients who underwent surgery for colore ctal cancer were retrospectively analyzed by immunohistochemistry, and the coexpression of these protein markers was related to patient outcome. Results The risk of developing liver secondaries was correlated with the expression of nm23 protein (p < 0.0001); this was also the case in those patients wit h Dukes' stage B showing positive nm23 immunostaining (p = 0.006). The dete rmination of the number of positive markers or the cumulative intensity sco re did not improve the predictive value over and above that of nm23 protein alone. Conclusion Expression of nm23 protein is correlated with the risk of developing liver metastasis. Its evaluation alone may help to determine which patients who h ave undergone apparently curative resection of a colorectal cancer have an increased risk of liver recurrence, especially those with Dukes' stage B tu mors who might be considered for adjuvant chemotherapy.