Evaluation of sonographically guided percutaneous core biopsy of renal masses.
OBJECTIVE
Our objective was to determine the utility of sonographically guided percutaneous core biopsy to evaluate renal masses.


METHODS
We conducted a retrospective analysis of our imaging-guided procedures from January 1999 to June 2001. We performed 26 sonographically guided percutaneous core biopsies of renal masses in 26 patients. From two to five specimens were obtained from a single mass in each patient using an 18-gauge automated biopsy system. We examined the patients' medical records, pathology results, and imaging studies. Core biopsy results were compared with surgical pathology (n = 6) or clinical follow-up (n = 20).


RESULTS
All biopsies provided sufficient material for analysis. Biopsy findings were positive for malignancy in 19 (73%) of 26 masses. Histologic diagnoses included renal cell carcinoma were (n = 11), metastasis (n = 3), lymphoma (n = 2), and transitional cell carcinoma (n = 2). Specific cell type characterization could not be made on one biopsy, but the specimens were highly suspicious for malignancy. Biopsy revealed seven (27%) of 26 benign diagnoses: oncocytoma (n = 3), angiomyolipoma (n = 2), and fibrosis (n = 2). The average follow-up period for patients with benign diagnoses was 10 months. One case of surgically proven necrotic pyelonephritis was mischaracterized as fibrosis at core biopsy. Sonographically guided percutaneous core biopsy of renal masses showed a sensitivity of 100% and a specificity of 100% for the diagnosis of malignancy. The core specimens yielded a specific diagnosis in 92% (24/26) of masses. No immediate complications occurred after the procedure. One patient developed a pseudoaneurysm that presented 3 months after the biopsy. CONCLUSION. Sonographically guided percutaneous core biopsy is a reliable and accurate method for evaluating renal masses.
Department of Radiology, University of Michigan Medical Center, 1500 E. Medical Center Dr., Taubman Center 2910R, Ann Arbor, MI 48109-9723, USA.
Elaine M
EM
Caoili
Ronald O
RO
Bude
Ellen J
EJ
Higgins
Donna L
DL
Hoff
Hanh V
HV
Nghiem
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001707:Biopsy, Needle; D005260:Female; D006801:Humans; D007668:Kidney / Q000473:pathology*; D007680:Kidney Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed; D018084:Ultrasonography, Interventional