Editing Non-Muscle Invasive Bladder Cancer (section)

===== Efficacy =====
*'''<span style="color:#ff0000">No benefit of immediate chemotherapy on progression or survival[https://pubmed.ncbi.nlm.nih.gov/38265030/]</span>'''
**'''Only BCG has been shown to delay or reduce high-grade tumor progression.''' 
***No chemotherapy trials have achieved a significant reduction in progression
*'''<span style="color:#ff0000">Reduces risk of tumour recurrence</span>'''
**'''<span style="color:#ff0000">Number needed to treat to prevent 1 recurrence: 8 (absolute risk reduction ≈12%)'''
***'''<span style="color:#ff00ff">Meta-analysis evaluating immediate intravesical chemotherapy on risk of recurrence</span>'''
**** 13 studies including 2548 patients
**** '''<span style="color:#ff0000">Immediate intravesical chemotherapy</span>''' prolonged recurrence-free interval by 38% (HR: 0.62; 95% confidence interval [CI], 0.50-0.77; p<0.001; I(2): 69%), '''<span style="color:#ff0000">and early recurrences were 12% less likely in the intervention population''' </span>'''<span style="color:#ff0000">(ARR: 0.12'''; 95% CI, -0.18 to -0.06; p<0.001, I(2): 0%). '''The number needed to treat to prevent one early recurrences was 8''' (95% CI, 6-17 patients).
**** High risk of bias present in 12 of 13 publications. Quality of evidence for recurrence-free interval was very low and low for early recurrences.
**** Immediate post-transurethral resection of bladder tumor intravesical chemotherapy prevents non-muscle-invasive bladder cancer recurrences: an updated meta-analysis on 2548 patients and quality-of-evidence review. [https://pubmed.ncbi.nlm.nih.gov/29801011/ Perlis et. al.] Eur Urol. 2013 Sep;64(3):421-30.
*** '''<span style="color:#ff00ff">SWOG 0337 (JAMA 2018)'''
**** Population: ≈400 patients with suspected low-grade NIMBC undergoing TURBT 
**** Randomized to immediate post-TURBT intravesical instillation of gemcitabine vs saline
**** Outcomes
***** Primary: time to recurrence
***** Secondary: time to muscle invasion and death due to any cause
****Results
*****Time to recurrence: absolute risk reduction of 10-15% at 4 years
*****No significant difference in time to muscle invasion or death
****[https://pubmed.ncbi.nlm.nih.gov/29801011/ Messing, Edward M., et al. "Effect of intravesical instillation of gemcitabine vs saline immediately following resection of suspected low-grade non–muscle-invasive bladder cancer on tumor recurrence: SWOG S0337 randomized clinical trial." ''Jama'' 319.18 (2018): 1880-1888.]
*** '''Some have suggested that intravesical chemotherapy reduces overall cost of care by reducing the need for secondary resections. However, subsequent studies have shown that the tumors prevented are primarily smaller tumors that are often treated in the office or ambulatory surgery setting so the economic impact regarding recurrences remains controversial if recurrences are treated in any manner other than inpatient care'''
**'''<span style="color:#ff0000">Particularly effective for the initial presentation of a (3):</span>'''
**# '''<span style="color:#ff0000">Solitary</span>'''
**# '''<span style="color:#ff0000">Low-grade</span>'''
**# '''<span style="color:#ff0000">Papillary tumor</span>'''
** '''<span style="color:#ff0000">The incremental benefit in patients with recurrent or multiple tumors is limited.</span>'''
** '''<span style="color:#ff0000">No benefit has been found in patients with high-grade disease.</span>'''