Renal Pelvic Urothelial Carcinoma With Venous Tumor Thrombus: Prognosis and Reconsideration of TNM Staging.

PURPOSE: This study aims to summarize survival outcomes and identify prognostic factors for renal pelvic urothelial carcinoma (UC) with venous tumor thrombus (TT) involvement, and to explore its potential implications for the TNM staging system of upper tract urothelial carcinoma (UTUC).

METHODS

From January 2014 to August 2025, 473 cases of renal pelvic UC were reviewed from the Peking University Third Hospital database, with 37 cases (7.8%) identified as having venous TT. All patients underwent nephroureterectomy and thrombectomy. Propensity score matching at a 1:3 ratio was applied to identify comparable cases from the Surveillance, Epidemiology, and End Results (SEER) database.

RESULTS

In patients with renal pelvic UC and venous TT, the median progression-free survival (PFS) was 3.3 months, and the median overall survival (OS) was 12.8 months. The 1-year PFS and OS rates were 33.5% and 51.4%, respectively. Postoperative chemotherapy was associated with improved PFS (hazard ratio [HR] 0.32, 95% confidence interval [CI] 0.15-0.68), reducing the 1-year and 2-year mortality rates by 59% and 49%, respectively. Compared with T3 renal pelvic UC, T3 disease with venous TT showed significantly worse OS (P = .02). Notably, OS in patients with venous TT was comparable to that of T4 renal pelvic UC (P = .22). The presence of venous invasion was strongly associated with perinephric fat invasion (Fisher's test P < .0001).

CONCLUSIONS

Renal pelvic UC with venous TT is associated with adverse prognosis and survival outcomes resembling those of T4 disease. These findings highlight the need for reconsideration of TNM staging in this subset of patients and warrant further validation in larger, multicenter cohorts.