Clinical and pathologic prognostic indicators in colorectal cancer. A population-based study.

The institution of a colorectal Cancer Register in a health care district of Northern Italy gave the authors the opportunity to evaluate the prognostic relevance of several morphologic and clinical variables by univariate and multivariate analyses. Of the 134 patients registered in 1984, 132 were followed up until the end of 1989. Overall 5-year survival was 37%, but the figure increased to 43% when only colorectal cancer-related deaths were considered. Univariate analysis for clinical variables showed that TNM staging and age at diagnosis were significantly related to prognosis, whereas none of the other parameters were indicative of the clinical outcome. With a similar analysis, among the various morphologic variables, pattern of growth (infiltrating versus expanding) and extent of fibrosis (extensive versus little or absent) appeared to be indicators of prognosis. When the variables that were significant (stage, age, pattern of growth, and fibrosis) in the univariate analysis were entered into the Cox model of multivariate analysis, TNM staging was the only parameter that maintained an independent prognostic importance. The authors state that their results confirm the importance of stage in predicting survival for cancer of the large bowel and suggest that the possible prognostic value of clinical and morphologic variables should be investigated within each of the major TNM or Dukes' classes.