The effect of fibrin clot inhibitors on the immunomodulatory efficacy of Bacillus Calmette-Guérin therapy for non-muscle-invasive bladder cancer

Abstract

Objective: To determine if there is a difference in clinical outcomes among non-muscle-invasive bladder cancer patients taking fibrin clot-inhibiting (FCI) medications (aspirin, clopidogrel, or warfarin) while receiving Bacillus Calmette-Guérin (BCG) therapy compared with their counterparts not taking anticoagulation.

Materials and methods: Our Investigational Review Board-approved database was queried for patients who received an induction course of BCG from 2001 to 2011. The analysis included 224 patients with a minimum of 3 months of follow-up. Recurrence-free survival (RFS), cystectomy-free survival, overall survival, and disease-specific survival were analyzed using the Kaplan-Meier method stratified by FCI status. Logistic regression was used to predict the initial response rate to BCG and progression by FCI status.

Results: Of the 224 patients analyzed, 68, 19, and 23 patients were taking aspirin, clopidogrel and warfarin, respectively, at BCG induction. No specific FCI was associated with differences in cystectomy-free survival, overall survival, disease-specific survival, or the likelihood of progression at recurrence. Neither warfarin nor clopidogrel affected RFS. Patients taking aspirin trended toward increased RFS, although this was not statistically significant (P = .058). Multivariate analysis showed aspirin use was associated with an increased initial response to BCG (odds ratio, 2.41; P = .031)

Conclusion: Contrary to the postulated inhibitory molecular effect of FCI on BCG-binding activity, this study did not substantiate a significant impact on BCG efficacy of the concomitant use of these medications during BCG induction. The observation that aspirin use potentiates an increased initial response to BCG may warrant further analysis.