The Impact of Age on the Response of Patients With Superficial Bladder Cancer to Intravesical Immunotherapy

Abstract

We determined the influence of age on response to intravesical immunotherapy in patients with superficial bladder cancer. Data from a national phase II multicenter trial for BCG plus IFN-alpha intravesical therapy for superficial bladder cancer were analyzed. Recurrence-free survival 2 years after the initiation of therapy was examined in patients by incremental age decade. BCG-N patients received 81 mg BCG and 50 MU IFN-alpha, while patients who had previously been treated with BCG received a third of the BCG dose with 50 MU IFN-alpha and those who were BCG intolerant received a tenth of the BCG dose with 100 MU IFN-alpha. Kaplan-Meier survival curves were obtained. In all patients the largest difference in response was between the 289 who were 61 to 70 years old and the 123 who were older than 80 years with a 22% difference in cancer-free survival at a median followup of 24 months (61% vs 39%, p = 0.0002). When we assessed BCG-N and BCG treated patients separately in the 2 age groups, patients older than 80 years had a persistently lower response rate than younger patients 61 to 70 years old. Of BCG-N patients those older than 80 and younger than 50 years had the lowest cancer-free survival at a median followup of 24 months (47% and 45%, respectively). On multivariate analysis age was an independent risk factor for response. Aging appears to be associated with a decreased response to intravesical immunotherapy and is particularly apparent in patients older than 80 years. A potential explanation could be their depressed baseline immune status and consequent inability to mount an immune reaction to BCG or IFN-alpha.