Intravesical chemotherapy prophylaxis in primary superficial bladder cancer: a meta-analysis of 3703 patients from 11 randomized trials

The impact of intravesical chemotherapy prophylaxis on recurrence of superf icial transitional cell carcinoma of the bladder is poorly defined. The obj ective of this report is to present a meta-analysis of the available clinic al trial data to quantify the effect of intravesical chemotherapy on tumor recurrence following complete transurethral resection (TURB) in patients wi th newly diagnosed superficial bladder cancer. A prospective protocol outli ning the above meta-analysis was initially developed followed by a thorough search of the existing published literature using strict eligibility crite ria. Eleven randomized trials were found that met protocol specifications. These studies contained data on 3703 patients that were statistically combi ned using a fixed effects model (Peto). The outcome of interest was the pro portion of patients recurring at 1, 2, and 3 years post-TURB. Combining all 11 studies using 1-year recurrence as the outcome measure yielded a Peto o dds ratio (ORp) of 0.56, demonstrating a 44% reduction in 1-year recurrence among patients treated with intravesical chemotherapy versus those treated with TURB alone. A statistical test for heterogeneity (Q) showed these dat a to be heterogenous (the studies are not measuring an effect of the same s ize). Sensitivity analyses were performed to determine sources of heterogen eity. These tests suggest that chemotherapy treatment schedule may account for the wide variation in tumor recurrence rates across studies. When the a vailable clinical trial data were stratified by duration of treatment, the meta-analysis showed that intravesical chemotherapy decreased tumor recurre nce from 30% to 80% depending on the outcome of interest (i.e., recurrence at 1, 2, or 3 years post-TURB). Intravesical chemotherapy appears to have a major impact on decreasing the chance of recurrence of superficial transit ional cell carcinoma of the bladder. This is in contrast to prior analyses suggesting only modest efficacy in this clinical setting (i.e,, on the orde r of a 14% reduction in recurrence). (C) 2000 Elsevier Science Inc. All rig hts reserved.