Distinguishing adrenal metastases from benign lesions in NSCLC: the value of clinical and radiological parameters

Background: Lung cancer is the most prevalent malignancy worldwide and the leading cause of cancer-related deaths. The adrenal gland is a frequent site of metastasis in non-small cell lung cancer (NSCLC). The differentiation of adrenal metastases from benign lesions is imperative for accurate staging and treatment planning. Imaging methods such as FDG-PET/CT, CT, and MRI provide important diagnostic information; however, false negative and false positive results may occur with these methods. The employment of clinical, biochemical, and radiological predictors has the potential to enhance diagnostic precision. Methods: A retrospective cross-sectional study was performed on NSCLC patients diagnosed between 2015 and 2025. From 2,194 lung cancer cases, 121 patients who exhibited adrenal lesions on initial PET/CT and had no extrathoracic metastases were included. Clinical data (age, sex, T-N stage), biochemical markers (CEA, CA125) and radiological parameters (SUVmax, lesion size, laterality) were obtained. The relationship of these parameters with the presence of adrenal metastasis was systematically evaluated in order to identify potential predictors. Results: Of 121 patients, 86 had adrenal metastases and 35 had benign adrenal lesions. Malignant lesions demonstrated significantly higher SUVmax, larger size, and elevated CEA and CA125 levels. ROC analysis revealed optimal cut-off values: SUVmax > 3.05 (AUC = 0.86, sensitivity 89%, specificity 69%), CEA > 4.45 ng/mL, CA125 > 24.5 U/mL, and lesion size > 14.5 mm. Multivariate regression identified N3 stage (OR = 12.75, p = 0.043), elevated CEA (OR = 1.02, p = 0.038), and lesion size (OR = 1.09, p = 0.037) as independent predictors of metastasis. Most patients with metastasis were diagnosed at advanced stages, with 91.9% being T3–4 or N2–3. Conclusion: The present study demonstrates that SUVmax, lesion size, CEA, T stage, and N stage are significantly associated with adrenal metastasis in NSCLC. Integrated assessment of these clinical, biochemical, and radiological parameters can improve the differentiation of adrenal metastases from benign lesions, facilitating more accurate staging and treatment planning.