Value of Apparent Diffusion Coefficient (ADC) Ratio To discriminate Common Benign and Malignant Hepatic Focal Lesions at MRI diffusion study. 

Abstract

Background: Diffusion-weighted imaging (DWI) is a novel imaging technique with a growing application in onco- imaging. This modality evaluates the diffusion of water molecules in various tissues, which is restricted in hypercellular regions such as malignant tissue. Apparent diffusion coefficient (ADC) is a method that can quantify the degree of restriction in tissues and can have diagnostic roles in the characterization of hepatic lesions. The ratio of ADC values between a lesion and the background liver can potentially negate these external factors and provide a more accurate representation of change in the diffusion with respect to normal tissue. Aim: Our study aimed to investigate the usefulness of ADC ratio of a solid liver lesion to liver parenchyma to discriminate between benign and malignant lesions. Methods: This was a cross sectional study conducted on all patients with hepatic solid focal lesion (benign or malignant), starting from 10-2019 to 4-2020. All patients were subjected to: Full history taking including, Radiological investigations, and Laboratory investigations. Result: There was significant difference between benign and malignant group as regards lesion: liver ADC ratio. Conclusion: Lesion to background liver ADCratio is superior in discriminating between benign and malignant focal lesions compared to absolute ADC values of the hepatic lesions. With increasing ADCratio, there is a trend towards benignity. A cut off of ADCratio below 0.9 reflected malignancies while ADCratio above 1.5 reflected benign aetiology. These cut offs can be validated further with further studies with larger number of individual malignant and benign lesions.