PC status was analyzed in 304 consecutive patients with single intracapsular RCC. Degree and side of capsule penetration if present were evaluated. Mean (median, range) follow-up was 49 months (46, 25-69). Local recurrence rate, progression-free survival (PFS), and cancer-specific survival were the main outcomes. Statistical analyses included the Kaplan-Meier method, log-rank test, and univariate and multivariate Cox regression models.
Overall, 51% of RCCs had intact PC and free from neoplastic invasion (PC鈭?, 34.9% had capsular penetration on the parenchymal side (PCK), and 14.1% had tumor invasion on the perirenal fat tissue side (PCF). None of the patients had positive surgical margins. The 5-year PFS rates for tumors PC鈭? PCK, and PCF were 97.5%, 96.7%, and 77.1%, respectively (P<0.0001).
The multivariate Cox model showed PCF to be the sole significant independent predictor of PFS, whereas patients who had PCK did not present a significant increased risk in developing recurrence.
Tumor enucleation is an oncologically safe nephron-sparing surgery technique. PCF is a significant and independent predictor of tumor recurrence in patients with clinically intracapsular RCCs scheduled for nephron-sparing surgery. PCK does not predict the risk of recurrence.