PCNA, Ki-67, p53, bcl-2 and prognosis in intraoral squamous cell carcinoma of the head and neck.

Eighty patients with primary intraoral squamous cell carcinomas of the head and neck, with a follow-up of 4-14 years were analysed for clinical outcome in relation to immunohistochemical expression of PCNA, Ki-67, p53, bcl-2 and presence of mutations in the p53 gene. The tumor site was not associated with the different parameters calculated. PCNA and Ki-67 labelling showed median values of 56% and 32%, respectively, and neither antigen was of predictive value. Fifty-five percent of the tumours expressed p53, and 38 (48%) had mutations in the p53 gene. No association between the presence of p53 protein or mutations in the p53 gene and clinical outcome was found. Bcl-2 positivity was detected in a minor fraction (10%) of the tumours.