Combining 18F-FDG PET and Gd-EOB-DTPA-enhanced MRI for staging liver fibrosis.

Abstract Aim To evaluate the diagnostic performance of combining 18F-2-fluoro-2-D-deoxyglucose-positron emission tomography (18F-FDG PET) and gadolinium-ethoxybenzyl-diethylenetriamine-pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) for liver fibrosis staging. Materials and methods Male New Zealand white rabbits (n = 48) were treated with carbon tetrachloride (CCl4) to induce liver fibrosis, while control group rabbits (n = 8) received normal saline. The liver tissues of rabbits were histopathologically examined (classified according to the METAVIR classification system) for liver fibrosis staging and RT-PCR was used to ensure diagnostic accuracy. Integrated PET/MRI was performed. The mean standardised uptake value (SUVmean) and relative enhancement (RE) were evaluated for different liver fibrosis stages using a Mann-Whitney U test. The performance of PET/MRI was evaluated by using the receiver operating characteristic curve (ROC) and the area under the ROC curve (AUC). Key findings In total, 10, 16, and 8 rabbits classified into no fibrosis (F0), mild fibrosis (F1–2), and severe fibrosis (F3–4) categories, respectively. There were significant differences in SUVmean and RE between F0 and F3–4 and between F1–2 and F3–4 (p   0.5). Combined SUVmean and RE performed well in staging liver fibrosis, with AUC of 0.8 for F0 or greater, 0.744 for F0 or F1–2, 0.945 for F1–2 or F3–4, and 0.962 for F3–4. Significance Combining SUVmean and RE provides high accuracy for grading liver fibrosis, especially in the differentiation between F1–2 and F3–4. 18F-FDG and Gd-EOB-DTPA-enhanced PET/MRI could be a non-invasive diagnostic method to guide the selection of clinical treatment options.