Development of a Novel Scoring System Quantifies Opportunities to Reduce Surgery for Benign Renal Neoplasms: A Retrospective Quality Improvement Analysis within the MUSIC-KIDNEY Collaborative

Abstract

Purpose: Nonmalignant pathology has been reported in 15% to 20% of surgeries for cT1 renal masses. We seek to identify opportunities for improvement in avoiding surgery for nonmalignant pathology.

Materials and methods: MUSIC-KIDNEY started collecting data in 2017. All patients with cT1 renal masses who had partial or radical nephrectomy for nonmalignant pathology were identified. Category for improvement (none-0, minor-1, moderate-2 or major-3) was independently assigned to each case by 5 experienced kidney surgeons. Specific strategies to decrease nonmalignant pathology were identified.

Results: Of 1,392 patients with cT1 renal masses 653 underwent surgery and 74 had nonmalignant pathology (11%). Of these, 23 (31%) cases were cT1b. Radical nephrectomy was performed in 17 (22.9%) patients for 5 cT1a and 12 cT1b lesions. Only 6 patients had a biopsy prior to surgery (5 oncocytoma, 1 unclassified renal cell carcinoma). Review identified 25 cases with minor (34%), 26 with moderate (35%) and 10 with major (14%) quality improvement opportunities. Overall 17% of cases had no quality improvement opportunities identified (12 partial nephrectomy, 1 radical nephrectomy).

Conclusions: Review of patients with cT1 renal masses who underwent surgery for nonmalignant pathology revealed a significant number of cases in which this outcome may have been avoided. Approximately half of cases had moderate or major quality improvement opportunities, with radical nephrectomy for nonmalignant pathology being the most common reason. Our data indicate a lowest achievable and acceptable rate of nonmalignant pathology to be 1.9% and 5.4%, respectively. Avoiding interventions for nonmalignant pathology, particularly radical nephrectomy, is an important focus of quality improvement efforts. Strategies to decrease unnecessary interventions for nonmalignant pathology include greater use of repeat imaging, renal mass biopsy and surveillance.

Keywords: biopsy; kidney; nephrectomy; quality improvement.