p53 deletion as a genetic marker in urothelial tumor by fluorescence in situ hybridization.

In order to investigate the significance of p53 deletion, 42 specimens of transitional cell carcinoma were analyzed by interphase cytogenetics with a fluorescence in situ hybridization technique and compared with clinicopathological and cytochemical parameters. In total, 27 (64%) and 16 (38%) specimens demonstrated p53 deletion and overexpression, respectively. The p53 deletion was significantly correlated with grade (P < 0.01), stage (P < 0.05), S-phase fraction (P < 0.05), and DNA ploidy (P < 0.01), while p53 overexpression correlated only with grade (P < 0.05). The close correlation of p53 deletion with clinicopathological parameters suggests p53 deletion to be of clinical importance to indicate the malignant potential of human urothelial tumors.