Fatty pancreas on EUS: Risk factors, correlation with CT/MRI, and implications for pancreatic cancer screening.

Background and Objectives: Fatty pancreas (FP), traditionally perceived as a benign finding, has been undergoing scrutiny lately due to growing evidence linking it to various disease states, including increased risk for pancreatic cancer (PC). Methods: A retrospective study of patients who underwent EUS at a single institution from August 2007 to October 2023, conducted by one endosonographer with more than 25 years of experience. Focusing on individuals identified with FP during EUS, we compared these findings with corresponding findings on computed tomography/magnetic resonance imaging (CT/MRI) conducted within 3 months or 1 year prior to or following EUS. Results: Ninety-one patients were included and identified as having FP on their EUS exams. The most common indication for EUS was PC screening in high-risk patients (35.16%). At the time of conducting EUS, 65.93% of patients had a body mass index (BMI) ≥30, 63.73% had hypertension, and 32.96% had type 2 diabetes mellitus (DM). Of the 91 patients, 70 had CT or MRI done within 3 months of the EUS date, and only 15 (21.43%) had FP reported on imaging. All 91 patients had CT or MRI within 1 year, and only 16 (17.58%) had FP reported on imaging. Conclusion: Only 21.43% of patients had FP on their CT/MRI within 3 months despite EUS findings, suggesting either lower accuracy of CT/MRI compared to EUS in identifying FP or potential underreporting in a real-world setting, even in a tertiary care center. This discrepancy in reporting is noteworthy considering FP's role as a potential precursor to several important conditions and promoting pancreatic carcinogenesis pathways.