Neoadjuvant chemotherapy has become standard of care for cisplatin-eligible patients with muscle-invasive bladder cancer qualified to radical cystectomy, providing a modest increase in 5-year overall survival rate. Several regimens are being employed for neoadjuvant treatment, largely because of their efficacy in metastatic setting. There is however a scarcity of evidence on the optimal cytotoxic regimen for neoadjuvant chemotherapy.
We evaluated the efficacy of different protocols of neoadjuvant chemotherapy amongst patients who underwent radical cystectomy at our institution.
This is a single-center, retrospective, observational study including a cohort of 220 patients who underwent radical cystectomy between 2014 and 2020. The neoadjuvant chemotherapy cohort included 79 patients and was compared to the cohort of historical controls including 141 patients operated prior to routine administration of neoadjuvant chemotherapy and those who opted for upfront surgery.
Administration of neoadjuvant chemotherapy decreased the risk of overall and cancer-specific mortality HR = 0.625 (95% CI 0.414-0.944), p = 0.025 and HR = 0.579 (95% CI 0.348-0.964), p = 0.036. Rates of downstaging, complete responses, lymph node metastasis, extravesical extension and positive surgical margins significantly favored neoadjuvant chemotherapy. Out of cytotoxic regimens, dose-dense MVAC and gemcitabine-cisplatin were similarly efficacious providing 46.9% and 50% of downstaging to <ypT2N0 respectively, including 30.6% and 25% of complete remissions. However, only dose-dense MVAC was associated with reduction of all-cause and cancer specific mortality risk HR = 0.385 (95% CI 0.214-0.691) p = 0.001 and HR = 0.336 (95% CI 0.160-0.703), p = 0.004 respectively.
Our study implies that neoadjuvant chemotherapy with subsequent radical cystectomy provides significant improvement over upfront surgery in locoregional control and long-term prognosis of muscle-invasive bladder cancer. The urologic community should strive to maximize utilization of neoadjuvant chemotherapy, yet further research, including randomized control trials, is needed to validate superiority of dose-dense MVAC as the preferred regimen for cisplatin-eligible patients.
PloS one. 2021 Nov 03*** epublish ***
Artur Lemiński, Krystian Kaczmarek, Tomasz Byrski, Marcin Słojewski
Department of Urology and Urological Oncology, Pomeranian Medical University, Szczecin, Poland., Department of Oncology and Chemotherapy, Pomeranian Medical University, Szczecin, Poland.