Multi-Quadrant Biopsy Technique Improves Diagnostic Ability in Large Heterogeneous Renal Masses

Area of Science:

• Urology
• Oncology
• Pathology

Background:

• Percutaneous biopsy of large renal masses is susceptible to sampling errors.
• Heterogeneous renal tumors may yield nondiagnostic results or miss critical prognostic indicators.

Purpose of the Study:

• To compare the accuracy of a modified multi-quadrant percutaneous biopsy technique versus a standard technique for large renal masses.
• To evaluate the impact on nondiagnostic rates and detection of aggressive features.

Main Methods:

• Retrospective review of clinical and pathological data for patients with cT2 or greater renal masses (2009-2014).
• Multi-quadrant technique involved biopsies from at least 4 separate solid enhancing areas.
• Comparison of nondiagnostic findings, sarcomatoid features, and procedural complications.

Main Results:

• The multi-quadrant technique yielded 0% nondiagnostic biopsies versus 10.9% for the standard technique (p=0.007).
• Sensitivity for detecting sarcomatoid features was 86.7% with the multi-quadrant technique vs 25.0% with the standard technique (p=0.0062).
• No complications were reported with the multi-quadrant technique.

Conclusions:

• The multi-quadrant percutaneous biopsy technique is superior for large renal tumors.
• This method increases the identification of aggressive pathological features and reduces nondiagnostic biopsy rates.