Biopsy‐all strategy in patients with a renal mass: simulation of a randomised controlled trial

ObjectivesTo investigate the clinical benefit and cost‐effectiveness of a renal biopsy (RB)‐all strategy for patients with a renal mass, as in renal cancer the indication for upfront surgery (SUR) without previous RB invariably results in the overtreatment of patients with benign histology.Patients and MethodsA total of 1729 patients with clinical (c)T1–2 cM0 renal mass treated with SUR were included. To simulate a randomised clinical trial comparing patients who underwent SUR vs RB and subsequent treatment, a random binary variable assigned patients to Arm a‐SUR and Arm b‐RB. In Arm a‐SUR, patients are all treated with SUR; postoperative complications and costs are those recorded after surgery. In Arm b‐RB, we have assumed an 8–20% uncertain RB histology rate and a 0.07% RB‐related complication rate to build our simulation model. Patients are selected for RB and subsequently for surgery in case of malignant or uncertain RB histology; complications are those recorded after surgery in case of malignant or uncertain RB histology, but 0% in case of benign histology. The outcomes of the study were the rate of SUR avoided, the rate of Clavien–Dindo Grade specific complications avoided, and the net difference in per‐patient cost in Arm b‐RB relative to Arm a‐SUR. In all, 10 000 individual iterations of the simulation model were performed and among all iterations, the median and 95% confidence intervals were computed.ResultsIf a RB‐all strategy is implemented, the expected rate of SUR avoided is 6.7%. The rate of overall, Clavien–Dindo Grade >II, and Clavien–Dindo Grade >III complications avoided is 3.0%, 2.5%, and 0.5%, respectively, and the average net difference in per‐patient cost was −$840 (US dollars).ConclusionsThe non‐selective use of RB in patients with a renal mass avoids a significant number of SUR, a marginal but existing number of complications, and is associated with decreased healthcare expenditures.