The role of diagnostic biopsy in patients with a renal mass remains undefined. Prior survey studies have demonstrated that approximately 70% of urologists rarely or never perform renal mass biopsy (RMB) because of the risk of false-negatives and the belief that the results will not change their treatment recommendation.^1,2 While multiple studies have shown that RMB is safe and that the pathological concordance with final surgical pathology is high,³ no prior study has directly evaluated the utility of RMB in treatment decision making. Therefore, we designed a pilot study to assess how RMB results impact clinical decision making for patients with newly diagnosed renal masses, confidence in treatment choice, and discordance between patient and provider treatment preference. We also evaluated patient satisfaction with their decision to undergo RMB.

This was an Institutional Review Board-approved prospective cohort study performed at a single institution between October 2019 and October 2021. We included all patients with a renal mass (1–7 cm in size) referred for RMB by a staff urologist and consented to participate in the study. The decision for RMB referral was at the discretion of the urologist. All biopsies were performed by interventional radiology and all pathology was reviewed by a genitourinary pathologist. Patients and physicians completed questionnaires before and after the biopsy. The pre-biopsy questionnaires were completed at the time of initial consultation and the post-biopsy questionnaires were completed after biopsy pathology was discussed with the patient. The survey assessed willingness, confidence, and usefulness metrics using either a Likert scale (1–10) and or a decisional conflict scale (yes/no/unsure).

The final cohort included 22 patients (14 male, 8 female) with an average renal mass size of 3.1 cm (SD 1.4). Five patients were lost to followup (3 pre-RMB and 2 post-RMB). Six patients (32%) had benign RMB pathology, 11 (58%) had malignant pathology, and 2 patients (11%) had nondiagnostic results.

Prior to RMB, 100% of patients stated that “information from an RMB will help me decide how to treat my kidney tumor” and 91% (20) were willing to pursue an RMB (Likert score >5) prior to choosing a treatment. Only 36% (8) of patients were willing to accept a treatment without RMB (Likert score >5). Before RMB, 45% of patients were unsure of their treatment preference, and 25% who had a treatment preference were “not clear if this was the best choice.”

Figure. Graphical representation of patient and provider discordance in treatment preference.

Following RMB, 86% of patients stated that the RMB results helped “[them] make a decision about treatment,” 92% rated the RMB as useful (Likert score >5), and 71% selected their ultimate treatment preference at least in part because of their RMB result. All patients were “glad they had an RMB.”

For 28% of patients referred to RMB, physicians believed that RMB results were unlikely (Likert score <5) to change their treatment recommendation, 24% were ambivalent (Likert score 5), and 48% believed that RMB would change their recommendation (Likert score >5). After RMB, physicians found that RMB results were useful in recommending treatment (Likert score >5) for 80% of patients (12/15).

After RMB, 57% of patients and 40% of physicians selected a different treatment from their initial treatment choice pre-RMB (see Figure). Both benign and malignant biopsy results were associated with change in treatment preference. In 4/6 cases with benign RMB pathology and in 8/11 cases with malignant RMB pathology, at least 1 party (patient or physician) changed their treatment preference. Prior to RMB, we observed discordance between patient and physician treatment preference in 81% of cases, compared to 25% of cases after RMB.

The results of our study add to a growing body of literature supporting the clinical utility of preoperative RMB in patients with renal masses.^4,5 We observed that RMB results impacted both patient and physician decision making. Most patients were willing to have a biopsy prior to choosing a treatment, and ultimately 100% of patients who had RMB were satisfied with their decision. We also observed that in most cases, the physician perceived the results of RMB to be useful, and that the results led patients and physicians to change treatment preference in a substantial number of cases. The results of RMB also markedly reduced discordance in treatment preference between patients and physicians.

Our data suggest that RMB can be a useful tool for improving shared decision making between patients with renal masses and their physicians. Shared decision making is the foundation for delivering patient-centered care and establishing a strong physician-patient relationship. It also is the key to maximizing both patient and physician satisfaction in treatment decisions and outcomes. RMB is a safe and accurate procedure that has the ability to reduce rates of unnecessary surgery for benign tumors and overtreatment of indolent renal cell carcinomas.^4,5 We are hopeful that additional research on the utility of RMB will further refine the treatment of patients with renal masses.