[Analysis of p53 expression and DNA ploidy pattern in colorectal cancer]

An immunohistological staining for p53 conducted in 114 cases of colorectal cancer. The background risk factors such as pathological and DNA ploidy patterns were analized in all cases. p53 was found in 50.0% (57/114). There was a slight increase in p53 positive cases in the advanced cancers, but it was not statistically significant. Five-year survival rates of Dukes B and C were 42.2% for p53-positive cases and 67.2% for p53-negative cases. There was a statistical difference (p < 0.05), but none in the Dukes A group. Study of p53 in combination with DNA ploidy patterns revealed an even greater disparity in survival rates (p < 0.01) between p53-positive aneuploid cases and p53-negative diploid cases. These results indicate that the staining of p53 in conjunction DNA ploidy patterns may be a useful indicator of prognosis in the cases of colorectal cancer.