P53 MUTATIONS IN EGYPTIAN BLADDER-CANCER

Cancer of the bladder is a frequent malignancy in Egypt and other deve loping countries in which bladder infection with the parasite Schistos oma haematobium is common. Several epidemiological, histopathological and clinical characteristics of cancer of the Bilharzial bladder sugge st that it is distinct from bladder cancer seen in industrialized coun tries. Little is known, however, about molecular aberrations in Egypti an bladder cancer. We studied the status of p53 in a series of 25 case s of Egyptian bladder cancer using immunohistochemistry to detect the p53 protein and SSCP/sequencing to identify mutations in the p53 gene. Ten of 25 (40%) tumor samples showed a mutation by SSCP/sequencing. M utations were seen in both the squamous and transitional cell variants . The presence of mutations was associated with advanced stage of dise ase. Immunohistochemistry had a sensitivity of 70%, and a Specificity of 85% for detecting p53 mutations. Our data show that p53 mutations a re a common event in Egyptian bladder cancer, and may be an indicator of advanced disease. Immunohistochemistry is both sensitive and specif ic for detecting p53 mutations in this tumor, and may be used to asses s the prognostic value of p53 mutations in this disease.