Background: Chronic actinic cheilitis (AC) is a precursor of squamous cell carcinoma (SCC) of the lip.
Objectives: To evaluate the histopathological characteristics that may help to identify AC more susceptible to carcinomatous transformation, to assess the p53 protein expression in AC, and to determine the value of the p53 expression as a marker of transformation into SCC of the lip.
Methods: Seventy cases of chronic AC were reviewed, 31 of which were associated with SCCs. The samples were obtained from pathology reports of AC and SCC of the lip. Histopathology and immunohistochemical expression of the p53 protein were evaluated in isolated AC and in AC adjacent to SCC.
Results: The intensity of the inflammatory infiltrate in the corium was the only histopathological finding significantly associated both with the presence of an invasive tumor and with the degree of epithelial atypia. Most AC (85%) were immunoreactive to the p53 protein. The p53 protein expression in cheilitis was not statistically associated with any other histopathological criteria.
Conclusions: An intense inflammatory infiltrate in AC was predictive of an adjacent invasive SCC. In this study, the p53 protein immunoreactivity was not a marker of malignant transformation.