OnCo
ideasIdea

Bladder preservation for MIBC after perioperative EV + pembrolizumab complete response

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.

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.

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.
What would test it
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

Connected

9top