Preservation of cytometric DNA distribution and epithelial marker expression after tumor progression of human large bowel carcinomas.

Tumor specimens were obtained from seven patients with large bowel carcinomas at operation of the primary neoplasm and by resection of local recurrences or metastases 2 1/2 to 36 months later. All specimens were evaluated with regard to nuclear DNA distribution as measured by flow cytometry and expression of carcinoembryonic antigen (CEA), secretory component, epithelial IgA, and HLA-DR antigens, as determined by immunofluorescence staining of tissue sections. Both the DNA distributions and the immunohistochemical staining patterns were similar in the primary and secondary tumors. These findings are in keeping with a monoclonal or oligoclonal tumor progression in advanced large bowel carcinoma.