Jason A. Pietryga MD, Presenter: Nothing to Disclose

Alison J. Kim MD, Abstract Co-Author: Nothing to Disclose

Rendon C. Nelson MD, Abstract Co-Author: Consultant, General Electric Company Research support, Nemoto Kyorindo Co, Ltd Research support, Bracco Group Research support, Becton, Dickinson and Company Speakers Bureau, Siemens AG Royalties, Lippincott, Williams & Wilkins

To describe our clinical experience with ultrasound-guided biopsies of focal liver lesions and to determine if small lesion size (≤3cm), patient body habitus, or history of cirrhosis affect the rate of inconclusive/negative biopsy results.

This is an IRB-approved HIPAA-compliant study. A retrospective search identified 283 consecutive adults who underwent US-guided biopsy of a focal liver lesion with pathology results from 1/1/2011 to 7/31/2012. Medical records/PACS were reviewed to identify the lesion sizes, patients’ BMI, history of cirrhosis and prior malignancy, and biopsy results. Rates of inconclusive/negative biopsy results were compared between patients with lesions ≤3 vs. >3cm, obesity vs. no obesity, and cirrhosis vs. noncirrhosis. Correlation of results with history of prior malignancy was also performed. Statistical analysis of the comparisons was performed using a Fisher’s exact test with a p-value < 0.05 deemed significant.

15.5% (44/283) of the biopsies had inconclusive/negative results. 25% (11/44) of these patients went on to rebiopsy or excision of which 45% (5/11) were diagnostic of malignancy. 19.0% (29/153) of lesions ≤ 3cm had inconclusive/negative results vs. 9.4% (124/153) of lesions >3cm (p=0.02). 21.4% (18/84) of obese patients had inconclusive/negative results vs.13.1% (23/176) of nonobese patients (p=0.063). 52.9% (9/17) of cirrhotic patients had inconclusive/negative results vs. 13.2% (35/266) of noncirrhotic patients. 10.7% (21/197) of patients with a known cancer were diagnosed with a new additional cancer (i.e. new primary).

A minority (15.5%) of patients who underwent US-guided biopsy of a focal liver lesion had inconclusive or negative results. Having a lesion ≤3cm or a history of cirrhosis increases the rate of inconclusive/nondiagnostic results. Obesity may increase the rate of inconclusive or negative results. A significant minority of liver lesions in a patient with a known cancer represent disease from a new primary.

A negative or inconclusive biopsy of either a small liver lesion or a lesion in a patient with cirrhosis should undergo further work-up as it is associated with a significant false negative rate.

Pietryga, J, Kim, A, Nelson, R, Clinical Implications of Negative and Inconclusive Percutaneous Ultrasound-guided Biopsy of Focal Liver Lesions.  Radiological Society of North America 2013 Scientific Assembly and Annual Meeting, December 1 - December 6, 2013 ,Chicago IL. http://archive.rsna.org/2013/13025385.html