ABSTRACT
OBJECTIVES: There is no consensus about the follow-up schedule after 5-year cancer-free periods. In this study, we aimed to elucidate the risk factors for the recurrence in patients with non-muscle-invasive bladder cancer who remained cancer free for more than 5 years. METHODS: Data from six Japanese institutions were retrospectively reviewed. Among the patients with non-muscle-invasive bladder cancer who were treated with transurethral resection of bladder tumor between 1990 and 2013, those who had no recurrence for more than 5 years were included in this study. The Kaplan-Meier method and Cox hazards model were used to estimate recurrence-free survival and to determine the pathologic and clinical factors affecting late recurrence. RESULTS: In total, 434 patients were enrolled in this study. Of these patients, 55 patients (12.7%) experienced late recurrence. The median follow-up time was 8.9 years (interquartile range 6.9-11.3 years). Prior history of bladder cancer before the most recent transurethral resection was a significant predictor for late recurrence (hazard ratio 1.99 [95% confidence interval 1.13-3.47], P = 0.019), although other clinical factors including tumor grade, pathologic stage, tumor multiplicity, and current risk classification systems were not associated with late recurrence. CONCLUSIONS: Late recurrence after a long tumor-free period is not rare and it was not predicted by current risk classification systems. Only prior history of bladder cancer was a significant predictor for late recurrence in this study.
