Are there differences among bacillus Calmette-Guérin (BCG) strains regarding their clinical efficacy in the treatment of non-muscleinvasive bladder cancer? The jury is still out but the answer is likely no

摘要

The use of bacillus Calmette-Guérin (BCG) as an intravesical instillation has been a mainstay in the prevention of recurrences, as well as progression for non-muscle-invasive bladder cancer (NMIBC) and in particular, for high-risk disease. Whether all BCG strains are equal, or some are more equal than others, as questioned by Noon et al, has become critically relevant at a time of shortages in BCG supply. In Canada, BCG has been supplied by a limited number of companies (currently Merck only). With recent and previous shortages, whether the use of other strains of BCG for prophylaxis would result in similar outcomes is critical in order to increase the availability of BCG for patients and clinicians. We have reviewed the literature both in the tuberculosis, as well as in NMIBC fields. We conclude that, despite differences in genetic composition and immune responses induced, there is no robust evidence that different BCG strains would be associated with different outcomes. This holds true in terms of either protection against tuberculosis or for prevention of recurrence or progression of NMIBC.