p53 protein expression and proliferative activity in imprints of superficial transitional cell carcinoma of the bladder

OBJECTIVE: To investigate p53 protein expression and proliferative activity in imprints of tumor biopsies from superficial transitional cell carcinoma of the bladder in relation to the histologic grade of malignancy and recur rence status. STUDY DESIGN: The study group consisted of 70 cases of superficial transiti onal cell carcinoma of the bladder. In order to investigate p53 protein exp ression and Ki-67 expression, an immunocytochemical avidin-extravidin compl ex technique was performed using monoclonal antibodies p53 D0-7 and prolife rating cells correspondingly. RESULTS: Thirty-seven percent of superficial transitional cell carcinoma ca ses showed positive expression of p53 protein. No correlation was found bet ween p53 protein expression and grade of malignancy (P =.45). p53 Protein e xpression was statistically correlated with a high Ki-67 labeling index (Ln P<.001) and recurrence status (P <.001). Forty-seven percent of cases show ed a Ki-67 LI>25%. No correlation was found between a high Ki-67 LI and gra de of malignancy (P =.703). A significant difference in high Ki-67 LI betwe en recurrent and nonrecurrent tumors of the same grade (P<.001) and between recurrent and nonrecurrent tumors was found independently of grade (P <.00 1). CONCLUSION: These results on cytologic material could provide useful inform ation on the biologic behavior of superficial transitional cell carcinoma o ft he bladder at the time of diagnosis.