Oncological Outcomes of Neoadjuvant Gemcitabine plus Carboplatin versus Gemcitabine plus Cisplatin in Locally Advanced Bladder Cancer: A Retrospective Analysis

Purpose: Cisplatin-based neoadjuvant chemotherapy (NAC) is the standard of care in non-metastatic muscle-invasive bladder cancer (MIBC). There are limited data regarding the alternative choices for cisplatin-ineligible patients. This study has investigated the oncological outcomes of gemcitabine plus cisplatin (Gem/Cis) and gemcitabine plus carboplatin (Gem/Carbo) in this setting. Materials and Methods: One hundred forty consecutive patients with MIBC (cT2–T4a) receiving neoadjuvant Gem/Cis or Gem/Carbo before chemoradiation (CRT) or radical cystectomy (RC) were retrospectively evaluated between April 2009 and April 2019. Patients with ECOG performance status 2, creatinine clearance 60 mL/min, hydronephrosis, ejection fraction 50%, or single kidney received Gem/Carbo. The complete clinical response (cCR) and overall survival (OS) of NAC regimens were compared. Prognostic significance was assessed with Cox proportional hazards model. Results: In total, 79 patients (56.4%) received Gem/Cis. The cCR was not significantly different between Gem/Cis and Gem/Carbo regimens (38.7% vs. 36.2%, P = .771). After NAC, 79 patients (56.4%) received CRT, and other cases underwent RC. After a median follow-up of 43 months, patients in the Gem/Cis group had significantly better OS than Gem/Carbo (median OS: 41.0 vs. 26.0 months, P = .008). Multivariable Cox proportional hazards models identified cT4a stage (95% confidence interval [95% CI]: 1.001–4.85, hazard ratio [HR] = 2.08, P = .03) and cCR (95% CI: 0.26–0.99, HR = 0.51, P = .04) as the only independent prognostic factors of OS, and ruled out the type of NAC regimen. Conclusion: The choice of NAC (between Gem/Cis and Gem/Carbo) is not the predictor of survival and both regimens had similar cCR.