CONTEXT: The ablative effect of intravesical therapy is known for decades. However, the clinical feasibility and efficacy of chemoablation for non-muscle-invasive bladder cancer (NMIBC) have not become accepted. OBJECTIVE: To assess the treatment outcomes of chemoablation for NMIBC and to compare its safety with that of the standard treatment, transurethral resection of bladder tumors (TURBT) followed by intravesical therapy. EVIDENCE ACQUISITION: Multiple databases were queried in July 2022 for studies investigating the complete response (CR) rates and adverse events in NMIBC patients treated with chemoablation using mitomycin C (MMC), gemcitabine, epirubicin, or bacillus Calmette-Guérin. EVIDENCE SYNTHESIS: Overall, 23 studies comprising 1199 patients were eligible for this meta-analysis. Among these studies, 20 assessed the efficacy of chemoablation and three compared the treatment outcomes of MMC chemoablation versus standard treatment. Among patients treated with weekly administration of any agent, the pooled CR rates at initial assessment were 50.9% (95% confidence interval [CI]: 45.9-55.9) for the marker lesion and 47.5% (95% CI: 36.5-58.7) for well-selected NMIBC (ie, small tumors and/or a small number of tumors). Novel regimens for chemoablation such as MMC-gel (70.6%, 95% CI: 60.1-79.3) and an intensive MMC regimen (64.7%, 95% CI: 56.2-72.3) provided better CR rates in well-selected NMIBC patients. Comparable CR rates were noted irrespective of tumor multiplicity, whereas tumor size <5 mm was associated with a higher CR rate than tumor size ≥5 mm (odds ratio: 0.36, 95% CI: 0.17-0.79). The novel intensive MMC regimen resulted in lower rates of dysuria and urinary frequency than standard treatment. CONCLUSIONS: Despite the lack of long-term outcomes, chemoablation appears to be a promising treatment option for well-selected NMIBC patients and can potentially help avoid unnecessary TURBT, specifically in some elderly patients with intermediate-risk NMIBC. Further well-designed studies with larger cohorts are necessary to address the differential tolerability and long-term anticancer efficacy of this resurging approach. PATIENT SUMMARY: Bladder instillation therapy has a potential ablative effect for well-selected non-muscle-invasive bladder cancer. This can lead to the omission of an unnecessary surgical treatment.

Cancer Prognostics and Health Outcomes Unit Division of Urology University of Montreal Health Center Montreal Canada

Department of Urology Comprehensive Cancer Center Medical University of Vienna Vienna Austria

Department of Urology Comprehensive Cancer Center Medical University of Vienna Vienna Austria; Department of Urology Hillel Yaffe Medical Center Hadera Israel

Department of Urology Comprehensive Cancer Center Medical University of Vienna Vienna Austria; Department of Urology King Fahad Specialist Hospital Dammam Saudi Arabia

Department of Urology Comprehensive Cancer Center Medical University of Vienna Vienna Austria; Department of Urology Medical University of Silesia Zabrze Poland

Department of Urology Comprehensive Cancer Center Medical University of Vienna Vienna Austria; Department of Urology Okayama University Graduate School of Medicine Dentistry and Pharmaceutical Sciences Okayama Japan

Department of Urology Comprehensive Cancer Center Medical University of Vienna Vienna Austria; Department of Urology Paracelsus Medical University Salzburg University Hospital Salzburg Salzburg Austria

Department of Urology Comprehensive Cancer Center Medical University of Vienna Vienna Austria; Department of Urology The Jikei University School of Medicine Tokyo Japan

Department of Urology Comprehensive Cancer Center Medical University of Vienna Vienna Austria; Department of Urology University Medical Center Hamburg Eppendorf Hamburg Germany

Department of Urology Comprehensive Cancer Center Medical University of Vienna Vienna Austria; Department of Urology University of Verona Azienda Ospedaliera Universitaria Integrata Verona Italy

Department of Urology Comprehensive Cancer Center Medical University of Vienna Vienna Austria; Institute for Urology and Reproductive Health Sechenov University Moscow Russia

Department of Urology Comprehensive Cancer Center Medical University of Vienna Vienna Austria; Institute for Urology and Reproductive Health Sechenov University Moscow Russia; Hourani Center for Applied Scientific Research Al Ahliyya Amman University Amman Jordan; Department of Urology University of Texas Southwestern Medical Center Dallas TX USA; Department of Urology 2nd Faculty of Medicine Charles University Prague Czech Republic; Department of Urology Weill Cornell Medical College New York NY USA; Karl Landsteiner Institute of Urology and Andrology Vienna Austria

Department of Urology Comprehensive Cancer Center Medical University of Vienna Vienna Austria; Men's Health and Reproductive Health Research Center Shahid Beheshti University of Medical Sciences Tehran Iran

Department of Urology Comprehensive Cancer Center Medical University of Vienna Vienna Austria; Research Center for Evidence Based Medicine Tabriz University of Medical Sciences Tabriz Iran

Department of Urology IRCCS San Raffaele Hospital and Vita Salute San Raffaele University Milan Italy

Department of Urology The Jikei University School of Medicine Tokyo Japan

S H Ho Urology Centre Department of Surgery The Chinese University of Hong Kong Hong Kong China

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