S-phase fraction in superficial urothelial carcinoma of the bladder--a prospective, long-term, follow-up study.

Objective: To study, in addition to traditional tumor characteristics at diagnosis, the significance of DNA ploidy and S-phase fraction for tumor progression and tumor-related death in superficial carcinoma of the urinary bladder.

Material And Methods: Newly detected superficial bladder carcinomas (stage Ta-T1), from 195 consecutive patients were characterized according to stage, grade, tumor size, multiplicity, growth pattern, cytologic evaluation and random mucosal biopsies, as well as DNA ploidy and S-phase fraction as determined by means of DNA flow cytometry. The outcome of disease was evaluated using hospital charts and death certificates.

Results: During a median follow-up period of 98 months (range 1-160 months), 28 patients (14%) progressed to muscle-invasive or metastatic disease and 24 (12%) died from disease. In univariate analysis all factors studied, with the exception of the size and number of tumors at diagnosis, were significantly related to progress and tumor-specific survival. In multivariate analysis, however, S-phase fraction was the most significant prognostic factor. When 21 high-risk patients with T1G3 tumors who underwent early cystectomy were excluded, S-phase fraction remained the most important prognostic factor. DNA ploidy failed as an independent predictor of survival.

Conclusions: High S-phase fraction at diagnosis of superficial urothelial carcinoma of the bladder identifies patients at high risk of progression and death from disease.