Purpose: To investigate the effect of repeated transurethral procedures under general anesthesia on overall mortality in patients with non-invasive bladder cancer.Materials and methods: All Danish residents with non-invasive papillary urothelial carcinoma or primary urothelial carcinoma in situ diagnosed between 1 January 2000 and 1 January 2011 were included and followed until death or 31 March 2017. All transurethral procedures under general anesthesia, intravesical instillation therapy, recurrences and progression to invasive disease or cystectomy were recorded during follow-up. Associations between treatments and overall mortality were evaluated using multivariable regression analysis adjusted for age, gender, comorbidities and socioeconomic status. The effect of disease progression on mortality was removed by censoring patients at the time of progression or cystectomy.Results: Risk of death increased with the number of transurethral procedures under general anesthesia for Ta low- and high-grade tumors compared to patients who had only one procedure; after eight or more procedures the risk of death increased by 28% and 83%, respectively. There was no similar relationship for carcinomas in situ. In total, 36-52% of procedures under general anesthesia did not identify urothelial neoplasia.Conclusions: Repeated transurethral procedures under general anesthesia appear to be associated with increased risk of death in patients with primary non-invasive papillary urothelial carcinoma. Furthermore, a substantial number of procedures were without findings of neoplasia, indicating that too many patients are admitted for transurethral procedures under GA. Attempts should be taken to reduce unnecessary transurethral procedures under GA, e.g. by improved outpatient diagnosis of urothelial neoplasia.
Keywords: NMIBC; Non-invasive bladder cancer; TUR-BT; mortality; progression; recurrence.