KEYNOTE-B15 ctDNA analysis presented by Jonathan Chatzkel at #ESMO26, with Min Teo as discussant 🧬 In cisplatin-eligible MIBC, ctDNA+ before surgery meant almost no pCR with either regimen (3.7% with EV + pembro, 2.2% with cis/gem). Among ctDNA− patients, pCR was 72.4% with EV + pembro vs 43.7% with cis/gem. In the EV + pembro arm, patients who cleared ctDNA had 24-month EFS of 81% vs 33% with persistent ctDNA+. The postsurgery results replicate NIAGARA. Serial ctDNA could open the door to bladder-sparing and surveillance questions. #MRD #ctDNA #BladderCancer