Relationships between nodal status and cell kinetics, DNA ploidy pattern and histopathology of the deeply infiltrating sites in colorectal adenocarcinoma.

Tumor cell kinetics and DNA contents were investigated by in vitro labeling with bromodeoxyuridine (BrdU) and flow cytometry using paraffin-embedded specimens in both superficially (Sup) and deeply (Deep) infiltrating sites of 28 colorectal adenocarcinomas. Eleven were well differentiated and 17 were moderately differentiated adenocarcinomas. In moderately differentiated adenocarcinoma, histologic low grade types of Deep were frequently associated with lymph node metastasis, but the BrdU labeling indices (LI) or tumor DNA ploidy pattern did not correlate with nodal status. Among the seven aneuploid tumors of moderately differentiated adenocarcinoma, the BrdU LI and histology of Deep tended to correlate with nodal status. These findings suggest that the histology of Deep should have a greater significance than tumor cell kinetics or DNA contents. They also suggest that the tumor DNA ploidy pattern may be heterogeneous and divided into subgroups according to its cell kinetics or histology of Deep in relation to lymph node metastasis.