Analysis of guideline recommended use of renal mass biopsy and association with treatment.

ABSTRACT

INTRODUCTION: Renal mass biopsy (RMB) may not be indicated when the results are unlikely to impact management, such as in young and/or healthy patients and in elderly and/or frail patients. We analyzed the utility of RMB in three patient cohorts stratified by age-adjusted Charlson comorbidity index score (ACCI). MATERIALS AND METHODS: We identified patients with cT1a renal tumors in the National Cancer Database from 2004-2014. We combined age and Charlson-Deyo scores to identify young and/or healthy patients ('healthy-ACCI'), elderly and/or frail patients ('frail-ACCI'), and a reference cohort. We performed multivariable logistic regression to identify predictors of RMB and treatment. We evaluated the impact of RMB on management by analyzing the proportion of high-grade disease on final pathology as a surrogate for risk stratification. RESULTS: We identified 36,720 healthy-ACCI, 2,516 frail-ACCI, and 18,989 reference-ACCI patients. Healthy-ACCI patients were less likely to undergo RMB (7.5% versus 10.8%; p < 0.001) while frail-ACCI patients underwent RMB at similar rates (11.8% versus 10.8%; p = 0.14) compared with reference-ACCI patients. On multivariable logistic regression, in both healthy-ACCI and frail-ACCI patients, RMB was associated with decreased odds of surgical treatment, and increased odds of ablation and surveillance (all p < 0.01). In the frail-ACCI patients, higher grade disease at surgery was identified in the RMB cohort (32.9% versus 23.5%, p = 0.05). CONCLUSIONS: RMB is performed less frequently in healthy-ACCI patients compared with the reference cohort. RMB is associated with decreased odds of surgical treatment and increased odds of surveillance and ablation in all cohorts. In frail-ACCI patients who underwent surgery, RMB may provide additional risk stratification as these patients had lower rates of low-grade disease.