The prognostic significance of p53, PCNA, and Ki-67 for squamous cell carcinoma of the oral cavity.

Background: A common gene alteration in human malignancies is the mutation of the p53 gene. Through mutation p53 loses its function as a tumor suppressor and enables the tumor to proliferate. Ki-67 and PCNA are proliferation markers. The aim of this study was to find a reference to the prognostic significance of p53, Ki-67, and PCNA in squamous cell carcinoma (SCC) of the oral cavity. Material and methods: Samples from 64 patients of the Department of Otolaryngology/Head and Neck Surgery, University of Bergen, Norway, with histologically proven SCC of the oral cavity were submitted to immunohistochemical procedure. All carcinomas were untreated. Results: 59.3% of the patients showed a positive reaction for p53. Ki-67 and PCNA were expressed in about 68% of the cases, but with less staining intensity. No correlation could be found between the expression of the three antibodies and tumor factors such as tumor size, lymph nodes, degree of differentiation, recurrence and survival rate, the occurrence of second primaries, or the smoking habits of the patient. Conclusions: The expression of the tumor suppressor gene p53 and the proliferation marker PCNA and Ki-67 seem to have no prognostic significance in SCC of the oral cavity.