Expression of cell-cycle regulatory proteins and their prognostic value in superficial low-grade urothelial cell carcinoma of the bladder

Aims: Cell-cycle regulatory proteins are important indicators in determining progression trough the cell-cycle and progression to invasive cancer in patients presenting with superficial bladder cancer. We performed an immunohistochemical study in order to evaluate the prognostic value of the expression of p 16, p27, pRb, p53 and Ki-67 in superficial grade I and II papillary urothelial cell carcinoma of the bladder. Methods: p16, p27, p53, pRb and Ki-67 immunoexpression was studied in 14 pTa, 35 pTla and 7 pTlb bladder tumours at presentation and at recurrence of their tumours. The recurrence-free survival and the progression-free survival were analysed according to these regulatory cell-cycle proteins expression. Results: For survival in univariate analysis a high Ki-67 labelling index was a poor prognostic factor for recurrence free and progression-free survival (P = 0.0014 and P = 0.012, respectively). Ki-67 labelling index was also an independent recurrence-free survival prognostic factor (P = 0.0005). The p 16, p27, p53 and pRb immunoreactivity was not significantly associated with recurrence or progression rate in this group of bladder carcinomas. Conclusions: These data suggest that the Ki-67 labelling index can be a reliable marker in predicting recurrence and/or progression in superficial low-grade bladder carcinomas and may be relevant in planning adjuvant therapy. (C) 2002 Elsevier Science Ltd. All rights reserved.