Tissue samples evaluated with respect to expression of Pms2, Ercc1, Xpf or Ku86. Entire tissue sections were evaluated with respect to all crypt absorptive cells seen in the tissue or within all cells of epithelial origin within a cancer. Pms2, Ercc1 and Xpf were evaluated in triplicate sequential 4 micron tissues sections of the same tissue samples. Ku86 tissue samples were from similar, but not identical, tissues to those evaluated for Pms2, Ercc1 and Xpf. Tissue samples from patients at different risks for colon cancer, or from colon segments resected because of colon cancer, were labeled A, B, C, D, E, F, G and the number of tissue samples, from different patients, evaluated for protein expression are shown in parentheses under their label. The tissue samples were from colonic biopsies from patients who had (A) never had an adenoma; (B) 1 to 3 adenomas < 1 cm; (C) advanced neoplasia with either adenoma > 1 cm, villous adenoma, or adenoma with dysplasia; (D) previous colon cancer; or from colonic resections with (E) tissue sample 1 to 10 cm distant from an adenocarcinoma; (F) area marginal to the tumor; or (G) epithelial origin cells within the adenocarcinoma.