Densitometric evaluation of DNA content in colorectal cancer.

The aim of the present study was to provide information on the DNA content in colorectal tumours using densitometric techniques on histological samples and correlating the findings with age, sex, histological grade, stage, presence or absence of lymph-node metastasis and survival time. The distribution of DNA values was significantly related with the histological grade. Dukes' stage and infiltration of the peritumoral lymph-nodes. The distribution of DNA values was not significantly correlated with age and sex. From the data obtained in this study it can be concluded that evaluation of DNA content in colorectal adenocarcinoma can be used as a prognostic test that is complementary to histological investigation. The ploidy can provide information for classifying the degree of malignancy and can also be used to determine which tumours are biologically most aggressive.