Summary of findings for the main comparison. Bacillus Calmette‐Guérin (BCG) compared to mitomycin C (MMC) for Ta and T1 bladder cancer.
| BCG compared to MMC for Ta and T1 bladder cancer | |||||
|
Participants: Adults (≥18 years) with intermediate and high‐risk
non‐muscle invasive urothelial bladder cancer Setting: hospital Intervention: BCG Comparison: MMC | |||||
| Outcomes | № of participants (studies) | Certainty of the evidence (GRADE) | Relative effect (95% CI) | Anticipated absolute effects* (95% CI) | |
| Risk with MMC | Risk difference with BCG | ||||
|
Time to death from any cause (absolute effect size estimates based on
event rate at 5 years). Follow‐up: range 3.5–20 years |
1132 (5 RCTs) | ⊕⊕⊝⊝ Lowa,b | HR 0.97 (0.79 to 1.20) | Study population | |
| 210 per 1000c | 6 fewer per 1000 (40 fewer to 36 more) | ||||
|
Serious adverse effects Follow‐up: range 1.6–10 years |
1024 (5 RCTs) | ⊕⊕⊝⊝ Lowa,b | RR 2.31 (0.82 to 6.52) | Study population | |
| 7 per 1000 | 9 more per 1000 (1 fewer to 37 more) | ||||
|
Time to recurrence (absolute effect size estimates based on event rate
at 5 years) Follow‐up: range 3–20 years |
2616 (11 RCTs) | ⊕⊝⊝⊝ Lowa,b,d | HR 0.88 (0.71 to 1.09) | Study population | |
| 450 per 1000e | 41 fewer per 1000 (104 fewer to 29 more) | ||||
|
Time to progression (absolute effect size estimates based on event rates
at 5 years) Follow‐up: range 1.6–20 years |
1622 (6 RCTs) | ⊕⊕⊝⊝ Lowa,b | HR 0.96 (0.73 to 1.26) | Study population | |
| 112 per 1000c | 4 fewer per 1000 (29 fewer to 27 more) | ||||
|
Quality of life (measured using EORTC QLQ‐BLS24 at baseline and after each installation weekly for 6 weeks) |
110 (1 RCT) | Not estimablef | Not estimable | There was no evidence of a difference between BCG and MMC groups, except for abdominal bloating and flatulence, which was worse in the BCG group.f | |
| *The risk in the intervention group (and its 95% confidence interval) is
based on the assumed risk in the comparison group and the relative effect
of the intervention (and its 95% CI). CI: confidence interval; HR: hazard ratio; RCT: randomised controlled trial; RR: risk ratio. | |||||
| GRADE Working Group grades of evidence High certainty: we are very confident that the true effect lies close to that of the estimate of the effect. Moderate certainty: we are moderately confident in the effect estimate: the true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different. Low certainty: our confidence in the effect estimate is limited: the true effect may be substantially different from the estimate of the effect. Very low certainty: we have very little confidence in the effect estimate: the true effect is likely to be substantially different from the estimate of effect. | |||||
aDowngraded one level for study limitations: concerns with performance or detection bias (or both), as well as with regard to allocation concealment and selective outcome reporting.
bDowngraded one level for imprecision: 95% CI was consistent with the possibility for important benefit and large harm.
cThe assumed risk was based on five‐year mortality rate from Gardmark 2007.
dDowngraded one level for inconsistency: variation in point estimates or substantial heterogeneity among studies (or both).
eThe assumed risk is based on five‐year mortality rate based on Ojea 2007b
fMore detailed results on quality of life were not available (conference abstract only)