PCNA defined proliferative activity of epithelial tumor cells in adenomas of the colon.

Proliferative activity of epithelial tumor cells was evaluated with the use of immunohistochemistry and anti-PCNA monoclonal antibodies in alcohol fixed paraffin embedded sections of 44 colonic adenomas, including 33 tubular, 5 villous and 6 tubulovillous adenomas. The mean PCNA index was 24.7 +/- 10.9%, 24.8 +/- 6.2% and 24.8 +/- 14.0% in tubular, villous and tubulovillous adenomas respectively. In 12 tubular adenomas with dysplasia the mean PCNA index in areas with dysplasia was significantly higher (38.2 +/- 11.5%) as compared to areas without dysplasia (17.0 +/- 8.9%; p < 0.05). The results indicate that PCNA index of epithelial tumor cells is significantly increased in adenomas with high grade of dysplasia irrespective of histological type or size of the tumour.