Abstract

To evaluate the prognostic significance of PCNA and EGFR in colorectal carcinoma, the author analysed 66 colorectal carcinomas in paraffin sections immunohistochemically, using the monoclonal antibody PCNA and EGFR and compared with clinicopathological data. The mean PCNA index of colorectal carcinomas was 49.0¡¾10.8%. PCNA index had positive correlation with lymph node metastasis(p<0.001), distant metastasis(p<0.001), modified Dukes' stage(p<0.001), Jass new prognostic classification grouping(p<0.00l), TNM classification(p<0.001) and tumor size over 10.0cm(p<0.05), degree of histologic differentiation(p< 0.01), fibrosis(p<0.05), perineural invasion(p<0.05), lymphatic and vascular invasion(p<0.05). PCNA expression was more pronounced at the infiltrative margins of the tumor and tumor cells within the lymphatic or vascular channels. But there was no relationship between PCNA index and patients age, sex and tumor location, growth pattern, degree of peritumoral lymphocytic infiltration. The positivity of EGFR in colorectal carcinomas was 93.9% and there was an association between staining intensity and the extent of EGFR expression(rs=0.684, p<0.001) and PCNA index(rs=0.451 & 0.432, p<0.001). There was an association between staining intensity and the extent of EGFR expression and modified Duke's stage(p<0.001), Jass grouping(p<0.001), TNM classification(p<0.001), lymph node metastasis(p<0.001), fibrosis(<0.05), lymphocytic infiltration(p<0.05), lymphatics and vascular invasion(p< 0.01). These results suggest PCNA index and EGFR expression may be a useful prognostic factors in colorectal carcinomas. Knowledge af the percentage of PCNA-positive cells could be especially helpful in deciding to treat patients with adjuvant chemotherapy.

• Keywords: PCNA, EGFR, Colorectal carcinoma, Prognostic factor