[Immunohistochemical study of p53 and Ki-67 antigen expression in bladder carcinoma]

We examined the relationship between the expression of mutant p53 and Ki-67 antigens in urinary bladder transitional cell carcinoma and the pathological and clinical findings. Tissues were obtained from 28 patients with bladder carcinoma who underwent total or partial cystectomy. An ABC immunostaining method and two primary antibodies (DO-7 and MIB-1 antibodies) were used. The percentages of p53 and Ki-67 antigen-positive cells to the total number of cells were regarded as the p53 and Ki-67 labeling indices (LI) respectively. There were no statistically significant correlations between p53 LI and the histological grade or stage, although p53 LI increased slightly in the high grade and high stage group. There was a statistically significant correlation between Ki-67 LI and the histological grade and stage (p < 0.05). The correlation between p53 LI and Ki-67 LI was linear. Some cases had a p53 LI below the mean even though the Ki-67 LI was higher. The clinical course was characteristic of superficial bladder carcinoma initially, but progressed to invasive bladder carcinoma over the next several years. These results suggest that even cases initially diagnosed as superficial bladder carcinoma with a low p53 LI may progress to invasive bladder carcinoma in subsequent years. Therefore, it is important that the patient be followed-up.