Imaging of adrenal masses: from incidental detection to clinical decision-making. A radiologist’s evidence-based vade mecum

Background and aim: The widespread use of cross-sectional imaging has led to an increasing detection of adrenal masses as incidental findings. While most lesions are benign and non-functioning, a clinically relevant proportion may be hormonally active or malignant. Accurate imaging characterization is essential to guide management. This review provides an imaging-focused, evidence-based overview of adrenal mass evaluation, emphasizing radiological decision-making. Methods: A narrative review of contemporary literature was conducted, focusing on the role of ultrasound, computed tomography (CT), and magnetic resonance imaging (MRI) in adrenal lesion assessment. Validated imaging criteria, diagnostic accuracy, and modality-specific limitations were analyzed, integrating clinical and biochemical considerations. Results: Characteristic imaging features of common adrenal lesions, including adenomas, myelolipomas, and pheochromocytomas, are described. Less frequent but clinically significant entities are discussed. Strengths and limitations of imaging techniques are outlined, and practical imaging-based diagnostic strategies are proposed. Conclusions: A structured, multiparametric imaging approach allows confident characterization of most adrenal masses and supports appropriate multidisciplinary management. Awareness of imaging limitations is essential to avoid misclassification and unnecessary investigations.