Association of aberrant p53 and p21WAF1 immunoreactivity with the outcome of oral verrucous leukoplakia in Taiwan

The expression of p53 and p21(WAFI) in, 53 oral verrucous leukoplakias (OVL s), mostly non-dysplastic lesions, was investigated to ascertain the role o f such events in malignant conversion. Immunohistochemical analysis reveale d aberrant p53 and p21WAFI immunoreactivity in 51% (27 cases) and 75% (40 c ases), respectively. After an average follow-up period of three and a half years, histopathological examination revealed that 22 (42%) cases had devel oped oral squamous cell carcinoma (OSCC), 14 (26%) cases had undergone recu rrence, and 17 (32%) cases were free of disease. The oncogenic potential of th is subset of premalignant lesions warrants attention. A significant dif ference in the frequency of OSCC progression/recurrence was noted in lesion s bearing aberrant immunoreactivity of either p53 (93% vs 42%; P = 0.00008) or p21(WAF1) (80% VS 32%; P = 0,002) in comparison with lesions without im munoreactivity. This study suggested that the aberrant immunoreactivity of p53 and p21(WAFI) may represent important alterations of OVL and could affe ct the outcome of this lesion.