...we report the results from stage 1 of a phase II neoadjuvant trial of N+I for cisplatin-ineligible patients (pts) with UTUC….Three pts had confirmed pathogenic germline variants in mismatch repair genes (MSH2, n=2; MLH1, n=1), all of which achieved pCR (n=1) or ypTaN0 (n=2) and remained alive and disease-free at last follow-up.