Growth Fractions in Bladder Cancer Defined by Ki67: Association with Cancer Grade, Category and Recurrence Rate of Superficial Lesions

Abstract

Predicting future tumour behaviour has always been a major task when treating bladder cancer. Ki67 monoclonal antibody has been reported to be a good marker of proliferative activity in a variety of tumours. We have studied the association of growth fractions defined by the monoclonal antibody with tumour grade, category and recurrence rate of superficial lesions in 34 patients with bladder cancer and 15 normal controls. Mean Ki67 indexes (% stained cells) were 0.07 +/- 0.02% in normal urothelium, 1.27 +/- 1.55% in grade 1, 12.23 +/- 8.32% in grade 2 and 16.42 +/- 11.82% in grade 3 tumours, while the values were 5.45 +/- 5.87%, 12.66 +/- 9.81% and 17.18 +/- 12.41% in categories pTa, pT1 and T2-T3 respectively. Recurrence and non-recurrence groups of patients showed indexes of 13.29 +/- 9.49% and 4.15 +/- 5.0% respectively. Statistically significant differences in Ki67 values between normal urothelium and tumour, between tumours of different grades and categories as well as between recurrence and non-recurrence groups of patients led to the conclusion that Ki67 monoclonal antibody is a good tool in defining tumour behaviour in bladder cancer.