Upper tract urothelial carcinoma (UTUC) accounts for a substantially higher proportion of urothelial carcinoma cases in China than in Western populations. Although radical nephroureterectomy remains the standard treatment for UTUC, many patients become ineligible for cisplatin-based chemotherapy after surgery because of impaired renal function and other comorbidities. Furthermore, subgroup analyses from three major adjuvant immunotherapy trials have failed to demonstrate a significant disease-free survival (DFS) benefit in patients with UTUC, underscoring the urgent need for novel therapeutic strategies.

For nearly four decades, platinum-based chemotherapy has remained the standard first-line treatment for urothelial carcinoma (UC). However, its limitations—including modest survival outcomes and significant treatment-related toxicity—have persisted as major clinical challenges.