Risk factors for development of sterile haemorrhagic cystitis in canine lymphoma patients receiving oral cyclophosphamide: a case–control study

Abstract

AbstractSterile haemorrhagic cystitis (SHC) is a known risk of cyclophosphamide treatment; however, most canine reports are case series. This case–control study examined risk factors forSHCin dogs with lymphoma receiving oral cyclophosphamide. Twenty‐two dogs withSHCand 66 control dogs were identified. On univariate analysis,SHCrisk factors included age (P = 0.041), induction protocol (P = 0.021) and cumulative cyclophosphamide dose (P = 0.002). On multivariate analysis, increasing cumulative cyclophosphamide dose was associated with increased risk ofSHCand the ‘short’ induction protocol (protocol 1) was associated with decreased risk. Controlling for age and induction protocol, odds ofSHCincreased by 2.21 per 750 mg m−2increase in cyclophosphamide dose (P = 0.001).SHCfrom oral cyclophosphamide is a predominately delayed toxicity resulting from high cumulative doses.