Contemporary trends in percutaneous renal mass biopsy utilization in the United States

Patients with a renal mass traditionally proceed directly to surgery without a preoperative tissue diagnosis confirming malignancy. Many surgically treated renal masses represent benign tumors or indolent malignancies on final pathology. This has led to a growing body of literature supporting an expanded role for percutaneous renal mass biopsy (RMB). This study aims to characterize national trends in RMB utilization.

Patients undergoing renal biopsy during a 12-year period (2006-2017) in the Premier Hospital Database were captured using International Classification of Diseases, Ninth Revision and Tenth Revision codes. We restricted our analysis to patients with a concurrent diagnosis of a renal mass. We determined utilization rate, subsequent interventions within 90 days of biopsy, predictors of RMB, and 30-day RMB complication rates. We applied sampling weights and adjusted for hospital clustering to achieve a nationally representative analysis.

Among 115,511 patients who met the inclusion criteria, the annual number of RMB rose from 7,196 in 2006 to 11,528 in 2017; during this period, more than 3 times as many patients proceeded directly to surgery without a prior RMB. After RMB, 85,848 (74.32%) patients were not treated within 90 days. Of those treated, thermal ablation was more common than surgery (17,269 vs. 12,394). Trend analysis showed that patients with metastatic disease represented a decreasing proportion of patients receiving RMB (27.0%-21.8%; P < 0.001). Compared to patients who proceeded directly to surgery, RMB was more commonly performed in patients in the highest age group (80 years and older, 15.9% vs. 9.2%), unmarried (50% vs. 45.9%), with more medical comorbidities (Charlson comorbidity index ≥4, 30.9% vs. 17.4%), or with metastatic disease (24.5% vs. 10.4%). Multivariable regression analysis determined the primary predictor of RMB was the presence of metastatic disease. Hematuria was the most common complication present in 5.18% of patients followed by pneumothorax in 1.75%. All other complications were rare (<0.4%).

Although there has been progressive adoption of RMB for the management of renal masses in the United States, utilization remains relatively limited and differentially employed across the population based on both clinical and nonclinical patient factors. More research is needed to understand which factors are considered when determining whether to utilize RMB in the evaluation of a renal mass.