Downstaging guided neoadjuvant strategy shift and bladder preservation in locally advanced bladder cancer: A case report.

Background: The study of bladder preservation for muscle-invasive bladder cancer (MIBC) mainly focuses on the T2 stage, which remains difficult in the T3 and T4 stage. Pembrolizumab has been applied as neoadjuvant therapy followed by radical cystectomy for MIBC, gaining encouraging results in the phase II study. Disitamab vedotin, an antibody-drug conjugate (ADC), also achieved promising efficacy for refractory bladder cancer. However, the neoadjuvant therapy strategy of these drugs for bladder sparing remains further exploration. Case presentation: A patient with locally advanced MIBC at our institute underwent a neoadjuvant therapeutic regimen followed by transurethral resection of bladder tumor (TURBT) and concurrent chemoradiotherapy. In light of limited initial efficacy, we enacted an adaptive shift in the neoadjuvant treatment strategy, transitioning from a combination of gemcitabine, Conclusion: Proactive evaluation in the early stages of tumor downstaging can serve as a guiding principle for neoadjuvant strategies. This is the first successful case of neoadjuvant pembrolizumab combined with disitamab vedotin and chemotherapy in MIBC patients achieving complete response and bladder preservation.