PURPOSE: Percutaneous biopsy obtained from a single location is prone to sampling error in large heterogeneous renal masses, leading to non-diagnostic results or failure to detect poor prognostic features.
The purpose of this study was to evaluate the accuracy of percutaneous biopsy for large renal masses using a modified multi-quadrant technique (quadBX) compared to standard biopsy technique (sBX).
MATERIALS AND METHODS: Clinical and pathologic data for all patients with ≥ cT2 renal masses who underwent percutaneous biopsy from 2009 - 2014 were reviewed. The quadBX technique was defined as multiple core biopsies from at least four separate solid enhancing areas within the tumor. The incidence of non-diagnostic findings, sarcomatoid features, and procedural complications was recorded and concordance between biopsy specimens and nephrectomy pathology was compared.
RESULTS: A total of 122 biopsies were performed for 117 tumors in 116 patients (46 using sBX technique and 76 quadBX technique). Median tumor size was 10 cm (IQR 8-12). Biopsy was non-diagnostic in 5/46 (10.9%) sBX and 0/76 (0%) quadBX, p=0.007. RCC was identified in 96/115 (82.0%) tumors and non-RCC tumors were identified in 21 (18.0%). One complication occurred using the sBX technique;, no complications reported using quadBX technique. Sarcomatoid features were present in 23/96 (23.9%) of large RCC tumors studied. Sensitivity for identifying sarcomatoid features was higher using quadBX technique compared to the sBX technique, 13/15 (86.7%) vs. 2/8 (25.0%), p= 0.0062.
CONCLUSIONS: Multi-quadrant percutaneous biopsy technique increases the ability to identify aggressive pathologic features in large renal tumors and decreases non-diagnostic biopsy rates.
Written by:
Abel EJ, Heckman JE, Hinshaw L, Best S, Lubner M, Jarrard DF, Downs TM, Nakada SY, Lee FT Jr, Huang W, Ziemlewicz T. Are you the author?
Department of Urology, University of Wisconsin School of Medicine and Public Health, Madison, WI; Department of Radiology, University of Wisconsin School of Medicine and Public Health, Madison, WI; Department of Pathology, University of Wisconsin School of Medicine and Public Health, Madison, WI.
Reference: J Urol. 2015 Mar 30. pii: S0022-5347(15)03635-6.
doi: 10.1016/j.juro.2015.03.106
PubMed Abstract
PMID: 25837535