Partial nephrectomy for small renal masses: An emerging quality of care concern?

Purpose: The recent popularization of laparoscopic radical nephrectomy may beget underuse of partial nephrectomy. To evaluate this concern we used the SEER registry to characterize national practice patterns for the surgical management of small renal masses. Materials and Methods: Between 1988 and 2001, 14,647 patients with primary tumor size 7 cm or less were treated surgically for locoregional kidney cancer. The proportion of patients treated with PN was determined and stratified by year of diagnosis and tumor size. Multivariate models were developed to identify independent determinants of PN use and overall survival following surgical treatment of kidney cancer. Results: Overall 1,401 patients (9.6%) were treated with PN vs 13,246 (90.4%) who underwent total nephrectomy. For tumors 7 cm or less, the use of PN increased progressively between 1988 (4.6%) and 2001 (17.6%, p < 0.001). Despite this trend PN remained fairly uncommon even for the smallest renal masses. Among patients with tumors less than 2 cm, 14% underwent PN in 1988 to 1989 vs 42% in 2000 to 2001. For tumors 2 to 4 cm the corresponding proportions were 5% and 20%, respectively (p < 0.001). Younger patient age, smaller tumor size and more recent diagnostic year were independent determinants of PN use (all p values < 0.05). All cause mortality was similar for patients treated with PN vs TN (HR 0.9, 95% CI 0.8-1.1). Conclusions: Despite more frequent application during the last 2 decades, nationwide use of PN remains relatively uncommon, even for the smallest renal masses. Recognizing the favorable outcomes associated with preservation of renal parenchyma, our findings identify a possible quality of care concern that should be addressed by the urological community.