Combination of Ethoxybenzyl‐Diethylenetriamine Pentaacetic Acid‐Enhanced Magnetic Resonance Imaging and a Serum Biomarker Is Useful in the Diagnosis of Hepatic Sinusoidal Disorder After Chemotherapy Treatment

ABSTRACT Aim Sinusoidal obstruction syndrome (SOS), also known as “blue liver (BL),” is a common hepatic injury following oxaliplatin‐based chemotherapy in patients with colorectal liver metastases (CRLM). Early non‐invasive identification of SOS is essential for safe hepatic resection and improved outcomes; however, this remains clinically challenging. Methods We retrospectively analyzed 155 patients who underwent preoperative ethoxybenzyl‐diethylenetriamine pentaacetic acid‐enhanced magnetic resonance imaging (EOB‐MRI) and hepatic resection for CRLM between 2014 and 2022. Radiologists evaluated SOS on EOB‐MRI using a five‐point reticular signal grading scale. Aspartate aminotransferase to platelet ratio index (APRI) scores were calculated preoperatively. BL was confirmed intraoperatively based on characteristic liver discoloration. Correlations between EOB‐MRI scores, APRI, and clinical outcomes were analyzed using receiver operating characteristic curves, survival analysis, and multivariate statistics. Results Of 70 patients treated with preoperative oxaliplatin, 25 (35.7%) exhibited intraoperative BL. Overall survival was significantly worse in the blue liver group (p = 0.0338), although disease‐free survival did not differ significantly. Patients in the BL group had significantly higher APRI and EOB‐MRI scores (p = 0.0028 and p < 0.0001, respectively). The combined EOB‐MRI assessment and APRI had the highest diagnostic ability for BL detection, yielding an area under the curve of 0.806, with 78.0% sensitivity and 67.7% specificity. Patients with high scores in both modalities exhibited significantly poorer overall survival. Conclusion A combination of EOB‐MRI and APRI is a valuable non‐invasive tool for preoperative detection of SOS in patients with CRLM. This approach improves diagnostic accuracy, facilitates surgical planning, and may predict long‐term prognosis following hepatic resection.