{"entity":{"id":"idea-bladder-preservation-mibc","kind":"idea","name":"Bladder preservation for MIBC after perioperative EV + pembrolizumab complete response","aka":[],"tldr":"If the ADC-immunotherapy combination erases the tumour in more than half of patients before surgery, some may not need their bladder removed at all.","summary":"pCR 57% in EV-303 and high pCR in EV-304 raise the question that dostarlimab answered in dMMR rectal cancer: can complete responders skip surgery? Trials (e.g., SunRISe-4 arms, MODERN, and investigator-led bladder-sparing studies) are beginning to test cystectomy omission with ctDNA and MRI-guided surveillance.","asOf":"2026-09-07","links":[{"label":"ClinicalTrials.gov NCT03924895: EV-303 / KEYNOTE-905","url":"https://clinicaltrials.gov/study/NCT03924895"},{"label":"ClinicalTrials.gov NCT04700124: EV-304 / KEYNOTE-B15","url":"https://clinicaltrials.gov/study/NCT04700124"}],"tags":[],"related":[],"cancers":["urothelial"],"sections":[],"technologies":["mrd-testing","mri"],"targets":[],"drugs":["enfortumab-vedotin","pembrolizumab","signatera"],"companies":[],"institutions":[],"pathways":[],"terms":[],"trials":["ev-303","ev-304"],"people":[],"bottlenecks":[],"keyPapers":["paper-pembrolizumab-urothelial-n-engl-j-med-2017","paper-pembrolizumab-urothelial-lancet-oncol-2017","paper-ev-302-nejm-2024"],"journals":[],"dependsOn":[],"notes":[],"hypothesis":"Patients with clinical complete response (cystoscopy, MRI, ctDNA-negative) after EV + pembrolizumab can defer cystectomy with a 2-year bladder-intact event-free survival above 70%.","rationale":"Cystectomy carries major morbidity; response depth is now high enough that surveillance may be non-inferior for a selected group, as in rectal cancer organ preservation.","test":"Single-arm bladder-sparing trial with strict clinical complete response criteria and salvage cystectomy, compared against EV-303/304 outcomes; ctDNA (Signatera-type) as an eligibility and monitoring tool.","maturity":"early-clinical"},"route":"/ideas/idea-bladder-preservation-mibc/","neighbours":{"cancer":[{"id":"urothelial","kind":"cancer","name":"Bladder & urothelial cancer","route":"/cancers/urothelial/"}],"technology":[{"id":"mrd-testing","kind":"technology","name":"MRD / molecular residual disease testing","route":"/technologies/mrd-testing/"},{"id":"mri","kind":"technology","name":"MRI","route":"/technologies/mri/"}],"drug":[{"id":"enfortumab-vedotin","kind":"drug","name":"Enfortumab vedotin","route":"/drugs/enfortumab-vedotin/"},{"id":"pembrolizumab","kind":"drug","name":"Pembrolizumab","route":"/drugs/pembrolizumab/"},{"id":"signatera","kind":"drug","name":"Signatera","route":"/drugs/signatera/"}],"trial":[{"id":"ev-303","kind":"trial","name":"EV-303 / KEYNOTE-905","route":"/trials/ev-303/"},{"id":"ev-304","kind":"trial","name":"EV-304 / KEYNOTE-B15","route":"/trials/ev-304/"}],"paper":[{"id":"paper-ev-302-nejm-2024","kind":"paper","name":"EV-302: enfortumab vedotin plus pembrolizumab replaces chemotherapy as first treatment for advanced bladder cancer","route":"/key-papers/paper-ev-302-nejm-2024/"},{"id":"paper-pembrolizumab-urothelial-lancet-oncol-2017","kind":"paper","name":"First-line pembrolizumab in cisplatin-ineligible patients with locally advanced and unresectable or metastatic urothelial cancer (KEYNOTE-052): a multicentre, single-arm, phase 2 study","route":"/key-papers/paper-pembrolizumab-urothelial-lancet-oncol-2017/"},{"id":"paper-pembrolizumab-urothelial-n-engl-j-med-2017","kind":"paper","name":"Pembrolizumab as Second-Line Therapy for Advanced Urothelial Carcinoma","route":"/key-papers/paper-pembrolizumab-urothelial-n-engl-j-med-2017/"}],"bottleneck":[{"id":"b-surgery-radiation-innovation","kind":"bottleneck","name":"Surgery and radiotherapy cure most, get least","route":"/bottlenecks/b-surgery-radiation-innovation/"}]}}