Biologic characteristics of esophageal epithelial dysplasia assessed by proliferating cell nuclear antigen.

Abstract

Proliferating cell nuclear antigen (PCNA) correlates with the cell proliferative state. Using a PCNA specific monoclonal antibody, various malignant neoplasms have been assessed for cell proliferation and malignant potential. However, there are few studies regarding the expression of PCNA in esophageal dysplasia. PCNA expression was immunohistochemically determined in resected specimens from 27 patients with superficial esophageal carcinoma that contained areas with various degrees of dysplasia, carcinoma in situ (CIS), and carcinoma invading the mucosal layer. The authors estimated the cell proliferative activity and biologic characteristics of the basal and parabasal cells of these esophageal epithelial disorders. The degrees of PCNA labeling index (PCNA LI) of the basal layers were lower than those of the parabasal layers in normal epithelium and dysplastic lesions, respectively, whereas no difference in CIS was recognized between the two layers. The proportion of PCNA LI in the basal layer of moderate dysplasia was lower than that in the basal layer of severe dysplasia. Conversely, there were no statistical differences between severe dysplasia and CIS in both basal and parabasal layers. In terms of lymphocytic infiltration beneath the dysplasia, there was a close relationship between the degree of lymphocytic infiltration and the PCNA index of the basal and parabasal layers. PCNA expression may be a useful marker to reflect the biologic characteristics of esophageal dysplasia, suggesting that a high grade of dysplasia is as serious a lesion as esophageal carcinoma.