Efficacy of conduction hyperthermia in the treatment of non-muscle invasive bladder cancer: A systematic review.

INTRODUCTION: Intravesical treatment for non-muscle invasive bladder cancer (NMIBC) aims to reduce recurrences and stop progression. Hyperthermia-enhanced chemotherapy with devices like COMBAT BRS, Unithermia, and BR-TRG-I is a promising alternative to conventional Bacillus de Calmette Guerin (BCG) therapy.

OBJECTIVE: To systematically review the efficacy of hyperthermia generated by conduction devices in the treatment of NMIBC.

MATERIAL AND METHODS: The review followed the preferred reporting items for systematic reviews and meta-analyses guidelines. A search was performed in the PubMed, Cochrane Library, Scopus, and ClinicalTrials.gov databases. Two reviewers independently assessed the eligibility of candidate studies and abstracted data from studies that met the inclusion criteria. The primary endpoint was assessment of recurrence. Secondary objectives included evaluation of treatment progression and safety.

RESULTS: Thirty studies meeting inclusion criteria underwent data extraction. In intermediate-risk NMIBC patients, COMBAT versus mitomycin C (MMC) in normothermia revealed no superiority in reducing recurrence or progression. High-risk NMIBC patients using COMBAT achieved similar or superior outcomes to BCG. BR-TRG-I demonstrated superior results over normothermia in intermediate- and high-risk NMIBC patients. Unithermia proved less effective than BCG in high-risk NMIBC. Progression outcomes were promising with COMBAT and BR-TRG-I, but comprehensive analysis was limited due to inconsistent assessment across studies. Adverse events were primarily mild-moderate, with some device-specific differences.

CONCLUSIONS: Studies on conduction hyperthermia present great variability, which do not allow us to determine the superiority of 1 device over another in terms of recurrence, progression, and/or adverse effects. Further research with consistent administration protocols is crucial for definitive conclusions.