Hepatocellular Carcinoma Lesion Characterization: Single-Institution Clinical Performance Review of Multiphase Gadolinium-enhanced MR Imaging—Comparison to Prior Same-Center Results after MR Systems Improvements

Abstract

Purpose:To measure diagnostic performance in the detection of hepatocellular carcinoma (HCC) by using the most recent technology and multiphase gadolinium-enhanced magnetic resonance (MR) imaging and to compare with earlier results at the same institution. Materials and Methods:This retrospective study was institutional review board approved and HIPAA compliant. Informed consent was obtained. Between January 2008 and April 2010, 101 patients underwent liver transplantation and pretransplantation abdominal MR imaging within 90 days. Prospective image interpretations from the clinical record were reviewed for documentation of HCC, including size, number, and location. Liver explant histologic examination provided the reference standard for lesion analysis and was performed in axial gross slices in conjunction with the MR imaging report for direct comparison. Tumors were categorized according to size ( Ն 2 cm or , 2 cm), and MR imaging detection sensitivity, specifi city, predictive values, and accuracy were calculated according to category. The Fisher exact test was used to compare results from this study against prior reported results. Results:Thirty-fi ve (34.7%) of 101 patients had HCC at explant analysis. Patient-based analysis of all lesions showed a sensitivity and specifi city of 97.1% (34 of 35) and 100% (66 of 66), respectively. For lesions 2 cm or larger, MR imaging had a sensitivity and specifi city of 100% (23 of 23) and 100% (78 of 78), respectively. For lesions smaller than 2 cm, MR imaging had a sensitivity and specifi city of 82.6% (19 of 23) and 100% (78 of 78), respectively. Lesion-based sensitivity for all tumors was 91.4% (53 of 58) in the current study, compared with 77.8% in 2007 ( P = .07). For lesions smaller than 2 cm, the sensitivity was 87.5% (28 of 32) in the current study, compared with 55.6% previously ( P = .02). Conclusion:MR imaging remains a highly accurate diagnostic method for the preoperative evaluation of HCC, and detection of small ( , 2 cm) tumors has been signifi cantly improved compared with that of earlier studies.q RSNA, 20111 From the Departments of Radiology

Renal safety of intravenous gadolinium‐enhanced magnetic resonance imaging in patients awaiting liver transplantation

“…Although the FDA-approved dose of gadobenate is 0.1 mmol/kg, our institutional experience with "half-dose" gadobenate at 0.05 mmol/kg has demonstrated excellent performance in the imaging of chronic liver disease and HCC, while extending its safety to patients with severe renal insufficiency, including those receiving renal replacement therapy. 22,23 In addition, our protocol does not require a pre-MRI hydration protocol to prevent CIN; therefore, these patients did not receive any protocol-driven hydration before the MRI.…”

MRI of hepatocellular carcinoma: an update of current practices

“…Our own recent analysis of liver explant pathology versus prospective MRI staging of HCC demonstrated 97% sensitivity and 100% specificity for the detection of HCC. The detection rate of smaller (<2 cm) tumors, in particular, was noted to have improved from 55.6% in 2006 to 87.5% in 2010, largely secondary to technology updates related to graded improvements in MR sequence design and hardware (15). It should also be emphasized that this study was performed using prospective clinical interpretations from individual radiologists, unlike most studies that have used retrospective readings by one or more radiologists; prospective interpretations provides a better estimate of true performance of a test in a natural clinical environment.…”

“…The Organ Procurement and Transplantation Network (OPTN) committee has recommended minimum technical specifications for dynamic contrast-enhanced MRI of the liver, which are outlined in Table 1 We have previously described our techniques (15,19). We recorded each patient's weight and administered gadobenate dimeglumine (MultiHance, Bracco Diagnostics, Princeton, New Jersey, USA) at a dose of 0.05 mmol/ kg and an injection rate of 2 mL/s, followed by a 30-mL saline flush (also at 2 mL/s) using a dual-chamber power injector, with the objective of minimizing gadolinium dose while preserving R1 effects of a standard agent dose (16).…”

“…We used a real time bolus-triggered technique to acquire the arterial phase (19), followed by venous (60 s) and delayed phase (180 s) images. This contrast dosing strategy has been shown to retain excellent accuracy with respect to HCC detection (15).…”

“…Any developing method that is proposed to improve HCC detection rate should be compared against the reference standard of optimized, dynamic T1-weighted GRE with individually tailored arterial phase timing, which has shown sensitivities and specificities of >90%-95% in the peer-reviewed literature (15,(30)(31)(32).…”