RESUMEN
To determine the mutation of p53 in chemically induced carcinogenesis on albino mice in skin papilloma and tubular adenoma breast by immunohistochemistry. An experimental study. The animal house of Postgraduate Medical Institute and Pathology Department of King Edward Medical College University, Lahore, for the duration of 20 weeks, from 15 February, 2004 to 15 July, 2004. Twentyfive albino mice [male and female] were selected for a study on chemical carcinogenesis. These animals were divided into five groups [A-E], five animals in each. DMBA [Dimethylebenz[a] Anthracene] and TPA [Tetradecanoylphorbal- 13-Acetic Acid] [chemical carcinogens] were given to produce the tumors and mutation of p53 expression was evaluated on the tumors appearing during this period of carcinogenesis. Squamous cell papillomas and tubular adenoma breast were selected for this study. All the papillomas showed faint reactivity for immunomarker p53, while tubular adenomas were nonreactive. The results of this study show that p-53 is a marker for premalignant lesions and helps in selecting patients for constant monitoring, upon the clinical verification of these results