Sinusoidal Obstructive Syndrome Diagnosed With Superparamagnetic Iron Oxide–Enhanced Magnetic Resonance Imaging in Patients With Chemotherapy-Treated Colorectal Liver Metastases

Abstract

PURPOSE: To assess the predictive value of superparamagnetic iron oxide (SPIO) -enhanced T2-weighted gradient echo (GRE) imaging to determine the presence and severity of sinusoidal obstructive syndrome (SOS). PATIENTS AND METHODS: Sixty hepatic resection patients with colorectal metastases treated with chemotherapy underwent unenhanced magnetic resonance imaging (MRI) followed by T2-weighted GRE sequences obtained after SPIO. The images were reviewed in consensus by two experienced observers who determined the presence and severity of linear and reticular hyperintensities, indicating SOS-type liver injury, using a 4-point ordinal scale. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) with 95% CIs for the detection of SOS were calculated. RESULTS: Twenty-four of 60 patients had moderate to severe SOS on MRI. MRI achieved a sensitivity of 87% (95% CI, 66% to 97%), specificity of 89% (95% CI, 75% to 97%), PPV of 83% (95% CI, 63% to 95%), and NPV of 92% (95% CI, 77% to 98%). SOS was never found at surgery or histology in patients whose background liver parenchyma was normal on SPIO-enhanced MRI. CONCLUSION: SOS is present in a significant proportion of patients with treated colorectal metastases and is effectively detected on SPIO-enhanced T2-weighted GRE images.