Abstract: PUB206
Diagnostic Yield and Pathologic Spectrum of Percutaneous Kidney Mass Biopsy: A 10-Year Single-Center Experience
Session Information
Category: Pathology and Lab Medicine
- 1700 Pathology and Lab Medicine
Authors
- El-Bizri, Raina, Brown University, Providence, Rhode Island, United States
- Patel, Pooja V., Brown University, Providence, Rhode Island, United States
- Raker, Christina A., Brown University, Providence, Rhode Island, United States
- Nizami, Tarek, Brown University, Providence, Rhode Island, United States
- Shah, Ankur, Brown University, Providence, Rhode Island, United States
- Merhi, Basma Omar, Brown University, Providence, Rhode Island, United States
Background
Percutaneous renal mass biopsy (RMB) is increasingly utilized to characterize indeterminate renal lesions and guide clinical management.
Methods
We conducted a retrospective review of patients who underwent RMB performed by interventional radiology at Rhode Island Hospital between 2015 and 2025. Clinical and histopathologic data were analyzed to determine distribution of renal mass pathology. Characteristics were compared between malignant and benign findings using Fisher’s exact and the Wilcoxon rank sum test.
Results
A total of 96 patients underwent RMB during the study period. Diagnostic tissue was obtained in 95 cases (99.0%), one biopsy aborted due to bleeding. Clinical and procedural characteristics by RMB diagnosis are summarized in Table 1. Malignancy was identified in 77 patients (81.0%), while 18 biopsies (19.0%) demonstrated benign or non-neoplastic findings, including 9 normal renal tissue, 5 oncocytomas, 2 xanthogranulomas, 1 angiomyolipoma, and 1 abscess. Patients with malignant lesions were more frequently male compared with those without malignancy (57.1% vs. 16.7%, p=0.003).
Renal cell carcinoma (RCC) was the most common diagnosis, present in 58 cases (61.1%). Among RCC subtypes, clear cell predominated (44/58, 75.9%), followed by papillary (9/58, 15.5%), chromophobe (2/58, 3.4%), RCC with sarcomatoid features (2/58, 3.4%), and RCC with oncocytic features (1/58, 1.7%). Non-RCC malignancies included 13 metastatic carcinomas (13.7%), 4 lymphomas (4.2%), 3 undifferentiated carcinomas (3.2%), 1 leiomyosarcoma (1.1%), and 1 angiosarcoma (1.1%). Hematoma occurred in 10 patients, and 4 patients required blood transfusion. No biopsy- related deaths or nephrectomies occurred.
Conclusion
Renal mass biopsy provides high diagnostic yield and identifies non-clear cell and non-primary renal malignancies. These findings highlight its critical role in refining diagnosis, guiding management, and potentially avoiding unnecessary surgical intervention.