PROGNOSTIC VALUE OF KI-67 ANTIGEN AND P53 PROTEIN IN URINARY-BLADDER CANCER - IMMUNOHISTOCHEMICAL ANALYSIS OF RADICAL CYSTECTOMY SPECIMENS

Objective To investigate the role of tumour proliferation and p53 expr ession as a marker of survival in patients with urinary bladder cancer who undergo radical cystectomy. Patients and methods Samples were obt ained from 31 patients (29 men and two women, mean age 66.0 years, ran ge 46-80) with transitional cell carcinoma of the bladder who underwen t radical cystectomy. The 31 formalin-fixed radical cystectomy specime ns were stained immunohistochemically for Ki-67 antigen and p53 protei n using MIB1 and p53 antibodies, respectively, and the results correla ted with tumour grade, stages and prognosis. Results The Ki-67 index w as significantly greater in high-grade tumours and in those overexpres sing p53 (>20% positive nuclei). Patients whose tumour samples had a h igh Ki-67 index (>32%) had a significantly worse prognosis than those with a lower index (P<0.01). There was a similar correlation between K i-67 index and prognosis in high-risk patients (grade 3 and pT3-4; P<0 .05). Although the associations between tumour grade, stage and p53 ex pression were not statistically significant, patients whose tumour sam ples overexpressed p53 had a lower survival rate (P<0.05), No patients with tumours having a low Ki-67 and low p53 index (n=14) died of urin ary bladder cancer during the follow-up. Conclusion These results sugg est that immunohistochemical analyses for Ki-67 and p53 are useful pro gnostic indicators in patients with urinary bladder cancer who undergo radical cystectomy; the prognostic role of these markers was particul arly important in high-risk (grade 3 and pT3-4) patients.