A multi-institutional retrospective study of hyperthermic plus intravesical chemotherapy versus intravesical chemotherapy treatment alone in intermediate and high risk nonmuscle-invasive bladder cancer

Objective:To compare the efficacy and safety of hyperthermic intravesical chemotherapy(HIVEC)and intravesical chemotherapy(IVEC)in patients with intermediate and high risk nonmuscle-invasive bladder cancer(NMIBC)after transurethral resection.Methods:We included 560 patients diagnosed with primary or recurrent NMIBC between April 2009 and December 2015 at 1 of 6 tertiary centers.We matched 364 intermediate or high risk cases and divided them into 2 groups:the HIVEC+IVEC group[chemohyperthermia(CHT)composed of 3 consecutive sessions followed by intravesical instillation without hyperthermia]and the IVEC group(intravesical instillation without hyperthermia).The data were recorded in the database.The primary endpoint was 2-year recurrence-free survival(RFS)in all NMIBC patients(n=364),whereas the secondary endpoints were the assessment of radical cystectomy(RC)and 5-year overall survival(OS).Results:There was a significant difference in the 2-year RFS between the two groups in all patients(n=364;HIVEC+IVEC:82.42%vs.IVEC:74.18%,P=0.038).Compared with the IVEC group,the HIVEC+IVEC group had a lower incidence of RC(P=0.0274).However,the 5-year OS was the same between the 2 groups(P=0.1434).Adverse events(AEs)occurred in 32.7%of all patients,but none of the events was serious(grades 3–4).No difference in the incidence or severity of AEs between each treatment modality was observed.Conclusions:This retrospective study showed that HIVEC+IVEC had a higher 2-year RFS and a lower incidence of RC than IVEC therapy in intermediate and high risk NMIBC patients.Both treatments were well-tolerated in a similar manner.