Andrea Veltri MD, Presenter: Speakers Bureau, Eli Lilly and Company Speakers Bureau, Bayer AG

Irene Garetto MD, Abstract Co-Author: Nothing to Disclose

Carlo Gazzera, Abstract Co-Author: Nothing to Disclose

Enrico Bollito, Abstract Co-Author: Nothing to Disclose

Donatella Pacchioni MD, Abstract Co-Author: Nothing to Disclose

Alessandro Volpe MD, Abstract Co-Author: Nothing to Disclose

Mauro Papotti MD, Abstract Co-Author: Nothing to Disclose

The wider utilization of cross-sectional imaging has increased the detection of indeterminate cystic and solid enhancing renal masses (RM). Despite an accurate pre-operative radiological study, surgical extirpation still results in at least 20% of benignancy. Literature suggests that renal biopsy can be accurate and significantly impacting on clinical choices. Our aim is to evaluate the safety, accuracy and usefulness of image-guided core biopsy (CB) in the management of RM.  

In 258 consecutive patients (171 male; 16-88 y, m 65), 268 RM (10-160 mm, m 33; 19 cystic, 236 solid, 13 mixed) underwent CB (265 US-guided, 2 CT-guided, 1 US+CT guided), by coaxial technique (18G tru-cut needle inserted in a 17G styleted cannula). Major and minor complications (according to SIR criteria) were recorded. The result of 50 CB was not assessable, due to patients lost at follow-up. Of the remaining 218 RM, 101 underwent ablative treatments, so a gold standard diagnosis was not available. Therefore, accuracy was calculated on 117 CB, verified on the basis of histology after surgical resection (76), response to medical therapy (7) or outcome at imaging follow-up (3-104 months, m 35) (34: 25 benign and 9 malignant selected for active surveillance).  

No major complications occurred (namely, no seedings). 10 minor complications (7 small perirenal hematomas, 1 macrohematuria not requiring transfusion, 1 self-resolving intercostal arteriovenous fistula and 1 hematoma in the abdominal wall) were managed on an out-patient basis. Among the 218 assessable CB, the pathological diagnoses were 167 malignant (160 RCC, 4 NHL, 3 met) and 51 benign (38 renal cell tumors, including 28 oncocytoma and 7 AML). According to the above gold standard criteria, TP were 75/117, FN 7, TN 35, FP 0. Sensitivity, specificity and diagnostic accuracy were 91.4%, 100% and 94%, respectively. PPV was 100%, NPV 83.3%. 142/218 RM (65.1%) were managed other than surgically.  

CB is safe and accurate. We contribute to the growing number of series that are demonstrating the usefulness of CB in the clinical management of RM.

Since low specificity or pitfalls of imaging can affect characterization of RM, causing unnecessary surgical resections, CB should be considered in the clinical management of all indeterminate lesions

Veltri, A, Garetto, I, Gazzera, C, Bollito, E, Pacchioni, D, Volpe, A, Papotti, M, Core Biopsies of Renal Masses: An Accurate Tool for Managing all That Is Indeterminate.  Radiological Society of North America 2013 Scientific Assembly and Annual Meeting, December 1 - December 6, 2013 ,Chicago IL. http://archive.rsna.org/2013/13022804.html