Should intravesical Bacillus Calmette-Guérin be employed in transplant recipients with bladder carcinoma?

Bacillus Calmette-Guérin (BCG) exerts its antitumor activity through induction of pro-inflammatory cytokines, while immunosuppressive agents prevent organ rejection by suppressing pro-inflammatory and promoting anti-inflammatory responses. Thus, in the setting of transplant populations, the use of intravesical BCG for bladder cancer has the possibility of either promoting allograft rejection or being rendered ineffective by the action of immunosuppressive agents that block pro-inflammatory responses. We discuss the potential immunologic interactions between BCG and immunosuppression, and review relevant outcomes in renal transplant recipients with bladder cancer receiving intravesical BCG.