Venous invasion and down-regulation of p21(WAF1/CIP1) are associated with metastasis in colorectal carcinomas.

BACKGROUND/AIMS: Liver and lymph node metastasis the major prognostic factor in patients with colorectal carcinoma. The aim of this work was to search for tumor parameters which can be employed to predict whether this has occurred.

METHODOLOGY

A total of 211 patients with a colorectal carcinoma (Dukes' B group, 83; Dukes' C, 94; Dukes' D, 34) were investigated for 10 clinicopathological variables, as well as apoptotic activity, expression of Ki-67, p21(WAF1/CIP1), p53, bcl-2 and DCC proteins, and the c-Ki-ras mutations. Data were analyzed by univariate and multivariate statistics.

RESULTS

Lymph node metastasis-predictive models were developed using the venous involvement index (the number of vascular involvements per elastica van Gieson-stained slide; Odds ratio [OR], 2.38; 95% confidence interval [CI], 1.52-3.71; p=0.0001), tumor size (OR, 0.82; 95% CI, 0.70-0.97; p=0.0179), and p21(WAF1/CIP1) immunolabeled index (the percentages of positive tumor cells; OR, 0.76; 95% CI, 0.64-0.90; p=0.0011). Liver metastasis-predictive models were developed using the venous involvement index (OR, 2.40; 95% CI, 1.71-3.37; p=0.0000) and tumor location (rectum vs. colon; OR, 9.31; 95% CI, 2.41-36.01; p=0.0012).

CONCLUSIONS

Down-regulation of p21(WAF1/CIP1) as well as marked venous involvement, small tumor size and colonic tumor are associated with lymph node and/or liver metastasis. Criteria for assessment of metastasis risk provide a basis for additional treatment guidelines.