Sequencing of Renal Mass Biopsy and Ablation: Results from the National Cancer Database

We assessed current utilization and sequencing of renal mass biopsy (RMB) and thermal ablation for renal cell carcinoma (RCC) patients in the United States.

The 2004-2014 National Cancer Database was queried for adult patients with histopathologically diagnosed American Joint Committee on Cancer stage I RCC ≤5 cm undergoing RMB and thermal ablation. RMB sequencing was stratified into "staged RMB" (separate sessions for RMB/ablation) or "concomitant RMB" (same date RMB/ablation). Demographics, cancer variables and time trends were compared. Univariate and multivariable logistic regression identified predictors of concomitant RMB, and evaluated their impact on inpatient hospital stay and 30-day unplanned readmissions.

A total of 6,323 patients were included, of whom 2,913 (46.1%) underwent staged RMB and 3,410 (53.9%) underwent concomitant RMB. Concomitant RMB was more frequently performed until 2012, and staged RMB thereafter (trend p <0.001). In multivariable logistic regression models, private insurance, clear cell RCC, right-sided disease and smaller tumor diameter demonstrated higher probability of concomitant RMB. Furthermore, geographical differences across the United States were evident (concomitant RMB West/South Central region 64.6% versus New England 29.3%, multivariable p <0.05). Concomitant RMB was associated with greater odds of inpatient hospital stay (multivariable OR=1.42, 95% CI=1. 27-1. 60; p <0.001) and 30-day unplanned hospital readmissions (OR=1.55, 95% CI=1.07-2.27; p=0.022).

Staged RMB is more frequently performed in more recent years and is associated with lower odds of inpatient hospital stay and unplanned readmissions within 30 days. These potential benefits, combined with the potential to limit ablation of benign tumors, need to be weighed against additional health care costs and inconvenience associated with 2 interventions.