The Role of the Diffusion Sequence in Magnetic Resonance Imaging for the Differential Diagnosis between Hepatocellular Carcinoma and Benign Liver Lesions

Abstract

Background and aimTo assess the role of diffusion weighted imaging sequence (DWI), routinely used in hepatic magnetic resonance imaging (MRI) for the differentiation of hepatocellular carcinoma (HCC) from benign liver lesions.MethodsA number of 56 liver MRI examinations were retrospectively analyzed independently by two experienced radiologists, blinded to each other results. A total number of 70 Focal Liver Lesions (FLLs) assessed by liver MRI in 56 patients were included in the present study. All lesions were retrospectively analyzed by two experienced radiologists, independently from each other and who were not aware of the previous results given by using different imaging techniques. All included FLLs had a final histological diagnosis, or the final diagnosis was based on consensus reading by two experienced radiologists. The signal of the included FLLs was qualitatively appreciated on the b-800 sequences and on the apparent diffusion coefficient (ADC) map. The ADC value of each FLL was measured and the ADC ratio between the ADC value of the assessed FLL and that of the surrounding liver parenchyma was calculated.ResultsThe mean ADC value for benign FLLs as assessed by the two independent readers was 1.75 × 10−3 and 1.72 × 10−3. The mean ADC value for HCC nodules was 0.92 × 10−3 for the first reader and 0.91 × 10−3 for the second reader respectively. The mean ADC ratio for benign FLLs was 1.81 and 1.84 for the two readers, respectively. The ADC ratio for HCC nodules was 0.91 and 0.91, respectively. The ADC value is an indicator which is less prone to interobserver variability (correlation of 0.919→1). The ADC ratio has, as the analysis of the ROC curve shows, the best predictive value for differentiation between benign FLLs and HCC nodules. Analysis of the signal intensity on the DWI b-800 image alone is of no significance in differentiating benign FLLs from HCC nodules (p>0.005).ConclusionsThe ADC value and the ADC ratio assessed on liver DWI are useful diagnostic tools in the differential diagnosis of benign FLLs vs HCC nodules. Quantitative methods such as calculating the ADC value or ADC ratio have better diagnostic value than qualitative techniques.

Diffusion weighted magnetic resonance imaging of liver: Principles, clinical applications and recent updates

“…Lesion characterization: Several studies have attempted characterization of liver lesions using DW-MRI[ 33 - 38 ]. A general assumption is that ADC values are higher in benign lesions and lower in malignant liver lesions[ 33 - 36 ].…”

Added Value of Quantitative Apparent Diffusion Coefficients for Identifying Small Hepatocellular Carcinoma from Benign Nodule Categorized as LI-RADS 3 and 4 in Cirrhosis

“…It has shown potential value in the characterization of benign and malignant liver nodules. [13][14][15] Moreover, recent studies have suggested that ADC may be useful in predicting histopathological differentiation, 16 microvascular invasion, 17 and early recurrence of HCC. 18 Among the quantitative ADC values, mean ADC (ADC mean ) is commonly selected.…”

Diffusion MRI with quantification of ADC value in characterization of benign and malignant hepatic lesions and their correlation with cyto-histopathology

“…Various studies in the past have stressed upon usefulness of ADC values in characterization of liver lesions but with significant difference of opinion. [6][7][8][9][10][11][12][13][14][15] In the present study no significant difference or bias was seen in various age groups or genders. Malignant lesions had a mean ADC of 1.13(x10 (−3) mm 2 /s), while benign lesions had mean ADC value of 1.63(x10 (−3) mm 2 /s) .…”

“…5 However, few other studies have reported that differentiation and characterization of focal lesions particularly solid benign lesion from malignant lesions such as focal nodular hyperplasia (FNH) from hepatocellular carcinoma (HCC) on the basis of ADC value is not completely reliable as both can show overlapping result. [6][7][8][9][10][11] In the absence of a reliable cut off value of ADC in differentiation of solid benign lesions from malignant lesions, this study aims to evaluate the role of diffusion weighted magnetic resonance imaging and quantification of ADC value in characterization of focal liver lesions and to determine a cut off value of ADC with cyto/histopathological correlation.…”