Masahiro Tanabe MD, Presenter: Nothing to Disclose

Eduardo Almeida Cunha Costa MD, Abstract Co-Author: Nothing to Disclose

Marilia Fortes MD, Abstract Co-Author: Nothing to Disclose

Omid Yeganeh MD, Abstract Co-Author: Nothing to Disclose

Tanya Wolfson MS, Abstract Co-Author: Nothing to Disclose

Claude B. Sirlin MD, Abstract Co-Author: Research Grant, General Electric Company Speakers Bureau, Bayer AG Consultant, Bayer AG

Michael Simca Middleton MD, PhD, Abstract Co-Author: Consultant, Allergan, Inc Institutional research contract, Bayer AG Institutional research contract, sanofi-aventis Group Institutional research contract, Isis Pharmaceuticals, Inc Institutional research contract, Johnson & Johnson Institutional research contract, Synageva BioPharma Corporation Institutional research contract, Takeda Pharmaceutical Company Limited Stockholder, General Electric Company Stockholder, Pfizer Inc Institutional research contract, Pfizer Inc

The Liver Imaging Reporting and Data System (LI-RADS) released by the ACR is a comprehensive system for standardized interpretation and reporting of CT and MR examinations performed in patients at risk for hepatocellular carcinoma (HCC). The purpose of this study was to assess imaging outcomes of LR-2 (probably benign), LR-3 (intermediate probability for HCC) and LR-4 (probable HCC) observations. Specifically, we sought to determine the proportion of LR-2, LR-3, and LR-4 observations that, during clinical imaging follow-up and in the absence of treatment progress regress or remain stable in category code.

This was a retrospective, observational, longitudinal, single-center study of patients who underwent clinical CT or MRI examinations for surveillance for or diagnosis of HCC.

The final study cohort had 158 patients (87 men, 71 women; mean age 59.0 years). All patients had chronic liver disease, and most had cirrhosis. The patients had a total of 284 observations (LR-4 [n = 53], LR-3 [n = 170], and LR-2 [n = 61]). Among the 53 LR-4 observations, 18 (34%) progressed to LR-5 during follow-up (15 within six months, one within 12 months, two at more than 12 months), 25 (47%) remained stable, and 9 (17%) regressed in category. Among 170 LR-3 observations, 7 (4%) progressed to LR-5 during follow up (0 within six months, two within 12 months, and five at more than 12 months), 10 (6%) progressed to LR-4, 47 (28%) remained stable, and 106 (62%) regressed to LR-1 or LR-2. All 61 LR-2 observations remained stable or regressed during follow-up.

LR-2, LR-3, and LR-4 observations have different imaging outcomes. One-third of LR-4 observations progressed to LR-5 within 6 months. Most LR-3 observations remained stable or regressed. All LR-2 observations remained stable or regressed.

The LI-RADS categories were developed mainly by expert opinion. This study provides preliminary validation of the LR-2, LR-3, and LR-4 categories by showing that they have different imaging outcomes.

Tanabe, M, Costa, E, Fortes, M, Yeganeh, O, Wolfson, T, Sirlin, C, Middleton, M, Imaging Outcomes of Liver Imaging Reporting and Data System (LI-RADS) 2, 3 and 4 Categories on CT and MR Examination.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14013460.html