Proliferating cell nuclear antigen and p53 protein expression in submucosal invasive colorectal carcinoma

In some cases of early colorectal carcinoma, radical surgical resection might be required because of vessel invasion, distant metastasis, or inadequate surgical margin. To characterize submucosal invasive colorectal carcinoma, we investigated expression of PCNA and p53 protein. Sixty-seven patients who underwent curative resection of submucosal invasive colorectal carcinoma participated in this study. The PCNA labeling index (PCNA-LI) is determined at the deepest lesion of carcinoma. The expression of PCNA and p53 protein were analyzed according to clinicopathological factors. 1) The PCNA-LI was correlated to histological grade, depth of invasion or vessel invasion in polypoid type. 2) The flat type had significantly higher PCNA-LI (65.1+/-8.2%) and p53 protein expression (69.6%) than the polypoid type. 3) The PCNA-LI was higher in cases with lymph node metastasis than in these without lymph node metastasis. 4) Overexpression of the p53 protein was detected in all cases with liver metastasis. Our results suggest that in order to determine the treatment for the patients with submucosal invasive colorectal carcinoma, the expression of PCNA and p53 protein may be a useful biologic marker.