The impact of age on the response of patients with superficial bladder cancer to intravesical immunotherapy

Abstract

Purpose: We determined the influence of age on response to intravesical immunotherapy in patients with superficial bladder cancer.

Materials and methods: 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.

Results: 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.

Conclusions: 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.