Urinary collecting system invasion is a predictor for overall and disease-specific survival in locally invasive renal cell carcinoma

Objective: To examine the impact of urinary collecting system invasion (UCSI) on survival in patients with pathologic stage T3 renal cell carcinoma (RCC).

Materials and methods: We identified 1420 patients who underwent nephrectomy at a single institution between 1988 and 2008. Patients with pT3 RCC and data on UCSI were examined (n=303). Clinicopathologic variables were compared using chi-square tests, and a multivariate analysis using the Cox proportional hazards method was used to evaluate the relationship between UCSI and survival.

Results: Of 303 patients with pT3 RCC, 67 (22.1%) had UCSI. UCSI was associated with higher T3 substage, tumor size, lymph node metastasis, and sarcomatoid features, as well as a shorter 5-year overall (51.9% vs 30.4%; P=.003) and disease-specific survival (59% vs 33.9%; P<.001) compared with those without USCI. On multivariate analysis, UCSI was independently associated with overall (HR 1.49; 95% CI, 1.02-2.17) and disease-specific survival (HR 1.76; 95% CI, 1.15-2.68).

Conclusions: The presence of UCSI is independently associated with higher overall and disease-specific mortality in patients undergoing nephrectomy for pT3 RCC. Locally advanced tumors crossing an additional anatomic boundary into the urinary collecting system appear to represent a particularly aggressive form of disease. These data suggest consideration for including UCSI in the next TNM staging system for RCC.