The markers were not significant prognostic factors in the 25 pT1 tumours, for which the individual relative risks were 0.95 (CI 0.19–4.76) for p53 alteration, 2.34 (CI 0.55–10.03) for p16, and 1.90 (CI 0.51–7.09) for pRb. This evidence concerns the gene RB1 and neoplasm.