Non muscle invasive bladder cancer evidence based guidelines have been clearly established in terms of intravesical therapy (Canadian)
NMIBC non muscle invasive bladder cancer comprises Ta, T1x, cis and account for 75-80% of bladder cancer. Overall recurrence across all stages is 60-70% and the overall progression rate to a higher stage or grade disease is 20-30%. The 2 most important prognostic factors are stage and grade and 6 factors are used in EORTC tables to predict the risk of recurrence and progression: grade, stage, size, prior recurrence rate, concomitant cis, tumor number. TURBT (transurethral resection of bladder tumor) is very important and the resection must include complete macroscopic clearance with a sample depth including detrusor muscle to reduce understaging.
- All T1 and any HG (high grade) tumor must have a re-resection TURBT 2-3 weeks after the initial TURBT, even if the first resection had normal benign musclaris propria in the specimen
- Sylvester meta-analysis showed that one single dose of intravesical MMC (mitomycin C) within 6 hours of the first TURBT reduces recurrence from 48% to 37%, and is most effective for a low grade solitary papillary tumor
- The reduction in risk of recurrence with intravesical chemotherapy one dose within 6 hours is 15%
- Recurrent low grade Ta lesions can have a maintenance MMC schedule over 1-2 years, 6 week courses
- BCG immunotherapy is better than MMC and other intravesical chemotherapy at reducing recurrence (from 67% to 29%)
- BCG is the treatment of choice for cis, and induction course works in 70% cases
- The 5 year progression free survival after BCG is 78.5% in primary, concomitant or secondary cis
- A second induction course may be needed if the 6 week check cystoscopy shows residual disease or if there is late failure, and the 2nd course is effective 25% of the time
- The danger is a 7% actuarial progression risk with each further induction course
- BCG is the only schedule that can reduce progression, 27% risk reduction in TURBT + BCG v TURBT alone – however in subset analysis in order for this to happen maintenance BCG was needed for up to 36 months
- Therefore BCG is choice treatment for any/all high grade NMIBC but also intermediate risk NMIBC or even low grade Ta recurrences that have failed MMC
- BCG schedule (Lamm SWOG) is – 6 weekly doses 2-4 weeks after TURBT induction, followed by maintenance – 3 weekly cycles at 3 and 6 months, then every 6 months for up to 3 years
- At least 1 year of maintenance is needed in order for BCG to reduce progression, and ¼ or 1/3 dose reductions can be made depending on tolerance
- Immediate early cystectomy in recurrent high grade, cis is very reasonable especially with ileal neobladder as the gold standard treatment in most patients now.