Revisiting an Old Conundrum: A Systematic Review and Meta-Analysis of Intravesical Therapy for Treatment of Urothelial Carcinoma of the Prostate.

BACKGROUND: The optimal management of non-invasive (mucosal and/or ductal) urothelial carcinoma of the prostate remains elusive and there is a paucity of data to guide treatment. OBJECTIVE: Our objective was to systematically review and synthesize treatment responses to conservative management of non-invasive prostatic urothelial carcinoma using intravesical therapy. METHODS: A systematic literature search using MEDLINE, EMBASE, Cochrane Library, SCOPUS, and Web of Science databases from inception to November 2019 was performed. Risk of bias assessment was performed using the Newcastle-Ottawa scale for non-randomised studies. Pooled estimates of complete response in the bladder and prostate and prostate only were performed using a random effects model. Pre-specified subgroup analyses were generated to assess differences in complete responses for: BCG therapy vs other agents, ductal vs mucosal involvement, CIS vs papillary tumors and TURP vs no TURP. RESULTS: Nine studies including 175 patients were identified for inclusion in the systematic review and meta-analysis. All were retrospective case series and most evaluated response to BCG therapy. The pooled global complete response rate for intravesical therapy was 60%(95%CI: 0.48, 0.72), and for prostate 88%(95%CI: 0.81, 0.96). Pre-specified analyses did not demonstrate statistically significant differences between subgroups of interest. CONCLUSIONS: Management of non-invasive prostatic urothelial carcinoma using intravesical therapy yields satisfactory results. Caution should be taken in treating patients with papillary tumors and ductal involvement, as data for these populations is limited. TURP may not improve efficacy, but is required for staging. Current recommendations are based on low quality evidence, and further research is warranted.