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Radical cystectomy for the treatment of T1 bladder cancer: the Canadian Bladder Cancer Network experience.

BACKGROUND
Radical cystectomy may provide optimal survival outcomes in the management of clinical T1 bladder cancer. We present our data from a large, multi-institutional, contemporary Canadian series of patients who underwent radical cystectomy for clinical T1 bladder cancer in a single-payer health care system.


METHODS
We collected a pooled database of 2287 patients who underwent radical cystectomy between 1993 and 2008 in 8 different centres across Canada; 306 of these patients had clinical T1 bladder cancer. Survival data were analyzed using Kaplan-Meier method and Cox regression analysis.


RESULTS
The median age of patients was 67 years with a mean follow-up time of 35 months. The 5-year overall, disease-specific and disease-free survival was 71%, 77% and 59%, respectively. The 10-year overall and disease-specific survival were 60% and 67%, respectively. Pathologic stage distribution was p0: 32 (11%), pT1: 78 (26%), pT2: 55 (19%), pT3: 60 (20%), pT4: 27 (9%), pTa: 16 (5%), pTis: 28 (10%), pN0: 215 (74%) and pN1-3: 78 (26%). Only 12% of patients were given adjuvant chemotherapy. On multivariate analysis, only margin status and pN stage were independently associated with overall, disease-specific and disease-free survival.


INTERPRETATION
These results indicate that clinical T1 bladder cancer may be significantly understaged. Identifying factors associated with understaged and/or disease destined to progress (despite any prior intravesical or repeat transurethral therapies prior to radical cystectomy) will be critical to improve survival outcomes without over-treating clinical T1 disease that can be successfully managed with bladder preservation strategies.