Comparison of Long-term Outcomes for Young and Healthy Patients with cT1a and cT3a Renal Cell Carcinoma Treated with Partial Nephrectomy.

Partial nephrectomy (PN) is recommended for renal cell carcinoma (RCC) of <4 cm. We hypothesized that there is no difference in all-cause mortality (ACM) between cT1a, cT1b, and cT3a <4 cm RCC following PN. The National Cancer Database was interrogated to identify patients aged <60 yr with a Charlson comorbidity index ≤1 diagnosed between 2004 and 2017. Cox proportional-hazard models stratified for cT stage were used to predict 10-yr ACM. A total of 30 195 patients (25 121 cT1a, 4884 cT1b, and 190 cT3a <4 cm) who underwent PN with median follow-up of 64.36 mo (interquartile range 42.91-93.77) were included. Cox analysis revealed no significant difference in 10-yr ACM between cT1a and cT3a <4 cm (hazard ratio [HR] 1.05, 95% confidence interval [CI] 0.58-1.90; p = 0.88). However, the cT1b group had higher ACM (HR 1.31, 95% CI 1.15-1.48; p < 0.01). The positive surgical margin (PSM) rate was higher for cT3a <4 cm than for cT1a tumors (14.2% vs 6.3%; p < 0.01). However, there was no difference in 10-yr ACM rate between cT1a and cT3a <4 cm (10.9% vs 9.7%; p = 0.42). Our results suggest that PN is an option for cT3a RCC <4 cm, particularly in cases in which maximum nephron preservation is essential, such as patients with chronic kidney disease or a solitary kidney, although a higher PSM risk should be appreciated. PATIENT SUMMARY: We found that partial removal of the kidney for localized advanced kidney cancer is safe. The rate of surgical margins positive for the presence of tumor is higher in localized advanced kidney cancer than for less advanced cancers, but there was no difference in 10-year predicted mortality.