The changing importance of prognostic factors in bladder cancer during a long-term follow-up

A cohort of 505 patients with a transitional cell bladder cancer were followed up for over 9 years and clinical, histological and morphometric factors were related to survival. Several survival analyses were done by moving the start of the follow-up so that the first analysis started at the time of primary therapy and the last one after 9 years follow-up. T-category, WHO grade, papillary status and the density of tumour infiltrating lymphocytes had independent short-term prognostic value whereas mitotic index and standard deviation (S.D.) of nuclear area were independent long-term predictors up to 7 years after diagnosis. In papillary tumours S.D. of nuclear area and mitotic index were independent long-term predictors in contrast to T-category and WHO grade which were both short-term prognostic factors. In superficial tumours only mitotic index had independent long-term prognostic value. The results show that the prognostic information from the primary tumour biopsy specimen has long-term prognostic significance in transitional cell bladder cancer. The results particularly emphasize the importance of factors related to cancer cell proliferation as long-term predictors.