Sonographically guided renal mass biopsy: indications and efficacy

Area of Science:

• Urology
• Radiology
• Pathology

Background:

• Solid renal masses require accurate diagnosis for appropriate management.
• Percutaneous biopsy is an alternative to surgical intervention in select cases.

Purpose of the Study:

• To review the clinical indications, pathologic results, and success rate of sonographically guided solid renal mass biopsies.
• To evaluate the diagnostic yield of fine-needle aspiration and core biopsy techniques.

Main Methods:

• Retrospective review of 44 consecutive sonographically guided percutaneous renal mass biopsies performed between 1993 and 1998.
• Analysis of biopsy indications, needle types (22- to 18-gauge spinal needles for aspiration, 20- to 18-gauge core biopsy guns), number of passes, and complications.
• Correlation of cytologic and surgical pathology records for diagnostic accuracy.

Main Results:

• 82% of biopsies were diagnostic (36/44).
• Fine-needle aspiration yielded diagnostic results in 67% of cases, with an additional 6% from cell blocks.
• Core biopsy alone provided a definitive diagnosis in 28% of cases, with 18-gauge needles showing higher diagnostic reliability (P = .017).
• Common diagnoses included renal cell carcinoma (n=18), lymphoma (n=4), and metastatic carcinoma (n=6).
• Complications occurred in 9% of cases and were managed conservatively.

Conclusions:

• Sonographically guided biopsy of solid renal masses is safe and effective for specific clinical indications.
• Fine-needle aspiration can provide a diagnosis in many cases.
• Core biopsy, particularly with 18-gauge needles, is crucial for definitive diagnosis when aspiration is insufficient.