Katsuhiro Sano MD,PhD, Presenter: Nothing to Disclose

Utaroh Motosugi MD, Abstract Co-Author: Nothing to Disclose

Tomoaki Ichikawa MD, PhD, Abstract Co-Author: Consultant, DAIICHI SANKYO Group

Shintaro Ichikawa MD, Abstract Co-Author: Nothing to Disclose

Hiroyuki Morisaka MD, Abstract Co-Author: Nothing to Disclose

Kojiro Onohara MD, Abstract Co-Author: Nothing to Disclose

Tomohiro Takamura, Abstract Co-Author: Nothing to Disclose

Hiroshi Onishi, Abstract Co-Author: Nothing to Disclose

Nodules that appear hypointense on hepatocyte phase of gadoxetic acid-enhanced magnetic resonance imaging (EOB-MRI) and hypovascular on arterial-phase are often encountered in clinical practice. Such nodules cannot be diagnosed using routine imaging criteria. The pupose of this study was to elucidate the natural history over a long period of hypovascular nodules that appear hypointense on hepatocyte-phase EOB-MRI by focusing on hypervascularization.

In this study, 235 such nodules in 84 patients were examined. Hypovascularity of the nodules was confirmed using dynamic CT. All nodules were retrospectively examined using serial follow-up CT and MRI. examinations until hypervascularity was observed on arterial-phase dynamic CT or EOB-MRI, or CT during hepatic arteriography.

The mean follow-up duration was 702 days (range: 69 to 2085 days). Of the 235 nodules, 148 (63%) developed hypervascularization. The optimal cut off value of the size of hypervascularization was 10mm. Of the 102 nodules (=10mm or >10mm), 81 (79%) developed hypervascularizaion. The size of the nodules (=10mm or >10mm) and increase in size of the nodules were independent risk factors of hypervascularization by multivariate analysis. The 1-year cumulative risks of hypervascularization were 20% (=10mm or >10mm). These values were significantly differences.

About 80% of hypovascular and hypointense nodules on EOB-MRi (=10mm or >10mm) progressed to conventional hepatocellular carcinoma. Large nodular size (=10mm or >10mm) and increase in size of the nodules is the MR imaging findings that higher risk of hypervascularization.

About 80% of hypovascular and hypointense nodules on EOB-MRI with the size equal to 10mm or larger 10mm. Large nodular size (=10mm or >10mm) and increase in size of the nodules are the MR imaging findings that indicate higher risk of hypervascularization.

Sano, K, Motosugi, U, Ichikawa, T, Ichikawa, S, Morisaka, H, Onohara, K, Takamura, T, Onishi, H, The Outcome of Hypovascular and Hypointense Nodules on Hepatocyte-phase Gadoxetic Acid-enhanced Magnetic Resonance Imaging; When Does It become a Conventional HCC?: 5 Years' Experience.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14014715.html