The bacillus Calmette-Guérin (BCG) vaccine nearly halved the risk of progression among patients with non–muscle invasive bladder cancer (NMIBC) compared with transurethral resection of the bladder (TUR), but only among those with very high-risk disease.
The study compared BCG to TUR with or without chemotherapy with regard to disease progression. BCG had no significant effect among high-risk patients, after adjusting for a range of prognostic factors or repeat resection.
The positive effect of BCG on progression that was observed in the very high-risk but not high-risk group was based on new risk stratification criteria, according to lead author Paolo Gontero, MD, director of urology at the University of Turin, Italy.
The abstract, presented at the European Association of Urology (EAU) 2022 Annual Meeting this past weekend, was selected for special recognition by an EAU scientific review committee.
Clarifying BCG's Benefit
The benefits of BCG in NMIBC remain controversial. A 2002 meta-analysis, for instance, showed that BCG significantly reduced the risk of progression after TUR for patients with superficial bladder cancer receiving maintenance therapy, but a 2009 meta-analysis indicated that BCG was no better than mitomycin-C at delaying progression or improving overall or cancer-specific survival.
In the current analysis, Gontero wanted to clarify the potential role of BCG for bladder cancer. The investigators used the newly developed EAU high and very high prognostic factor risk groups to stratify patients.
They rretrospectively compared the impact of BCG in comparison with TUR with or without chemotherapy on progression among patients in the two highest-risk categories. They performed multivariate analyses to account for imbalances in potential prognostic factors for progression within each group.
Among 4821 patients with NMIBC for whom complete data were available, 1657 were deemed high-risk, and 368 were considered very high-risk.
Overall, 58 of 269 patients (21.6%) in the very high-risk group who received BCG experienced disease progression, compared with 31 of 99 (31.3%) who received TUR with or without chemotherapy (hazard ratio [HR], 1.93).
In contrast, among high-risk patients, 112 of 905 patients (12.4%) who received BCG experienced disease progression, compared with 69 of 752 (9.2%) who received TUR with or without chemotherapy (HR, 0.91; 95% CI, 0.66 – 1.26). Within the high-risk group, the lack of significant effect of BCG remained after adjusting for pathologic prognostic factors and repeat TUR.
According to Morgan Rouprêt, MD, PhD, of the Sorbonne University in Paris, who was not involved in the research, "the EAU current guidelines promoted a new stratification which is much more accurate to identify the patients who are at extremely high risk to progress."
The take-home message, said Rouprêt, is that "in a period of shortage of BCG, we should restrict the use of the dose to the patients who are at very high risk according to the guidelines."
No source of funding for the study was reported. Gontero has relationships with Ferring, Arguer, Ipsen, and Astellas. Rouprêt has disclosed no relevant financial relationships.
European Association of Urology (EAU) 2022 Annual Meeting: Abstract A0234. Presented July 1, 2022.
Neil Osterweil, an award-winning medical journalist, is a long-standing and frequent contributor to Medscape.
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Cite this: Neil Osterweil. BCG Vaccine Benefit in Non–Muscle Invasive Bladder Cancer? - Medscape - Jul 05, 2022.