Stereologic estimates of volume-weighted mean nuclear volume in colorectal adenocarcinoma: correlation with histologic grading, Dukes' staging, cell proliferation activity and p53 protein expression.

Colorectal cancer has been studied from the point of view of the relationships between several variables, including proliferative activity and p53 protein expression. However, stereologic evaluation of nuclear size has not been thoroughly described. In the present study, measurements of the volume-weighted mean nuclear volume (nuclear Vv), have been performed in well, moderately and poorly differentiated colorectal adenocarcinomas and correlated with the Dukes' stage and other factors such as proliferative activity and p53 protein immunoreactivity. Although the mean values of nuclear Vv were higher in poorly differentiated cancers or Dukes' C&D stage than in well and moderately differentiated tumors or Dukes' A&B stage, these differences were not significant. However, the variability of nuclear size in colorectal cancers was more relevant than the mean values of nuclear Vv with respect to their invasive classification. The carcinomas which extended beyond the serosa (Dukes' stage C&D) had higher biologic variation than those grouped as Dukes' stage A&B. The results of the present study also indicate that nuclear size in colorectal cancers has a positive correlation with both proliferative activity and p53 protein expression. The relationship between nuclear Vv and proliferative activity emphasizes the possible prognostic relevance of this stereologic estimate of nuclear size in colorectal adenocarcinoma.