Combination therapy with intravesical bacillus Calmette-Guerin (BCG) plus interferon-alpha2b (IFN-alpha2b) for superficial transitional cell carcinoma (TCC) seems to be immune-dependent and activation of Th1 immune response is required for clinical efficacy. The present study evaluates circulating serum cytokine profiles (Th1/Th2 cytokines IFN-gamma, IL-2 TNF-alpha, IL-4, IL-6 and IL-10) in 41 bladder cancer patients prior to transurethral resection of tumor (TURBT) (pre-therapy), and following intravesical combination immunotherapy (post-therapy) and their association with recurrence. Mean levels of IL-2 and TNF-alpha were significantly reduced while IL-4, IL-6 and IL-10 were significantly enhanced in pre-therapy samples as compared to controls. Mean levels of IFN-gamma, IL-2 and TNF-alpha were significantly increased while IL-4 and IL-10 were significantly reduced in patients after instillation of combination immunotherapy. These findings suggest that bladder cancer patients develop Th2 dominant status with deficient type 1 immune response that shows tendency to reversal following therapy.