The value of macrophage inhibitory cytokine‐1 level in differentiating benign from malignant solitary pulmonary nodules

Macrophage inhibitory cytokine-1 (MIC-1), a transforming growth factor-β superfamily cytokine, is involved in tumor pathogenesis, and its measurement can be used as a clinical tool for the diagnosis of a wide range of cancers.The aim of this study was to explore the diagnostic value of serum MIC-1 in patients with solitary pulmonary nodules (SPNs).Serum specimens from 158 malignant SPN patients, 110 benign SPN patients, along with 120 healthy volunteers. The levels of serum MIC-1 were measured by sandwich enzyme-linked immunosorbent assay.Serum levels of MIC-1 in malignant SPN patients were significantly higher than those in benign SPN patients (P < .01), or those in healthy volunteers (P < .01). With a cutoff of 685.8 pg/ml, the sensitivity and specificity of MIC-1 in differentiating between malignant SPN patients and benign SPN patients, and between malignant SPN patients and healthy volunteers was, 56.3% and 92.7%, and 65.8% and 96.7%, respectively. An area under the curve (AUC) for malignant SPN resulting from MIC-1, which was significantly better than any other tumor markers tested including carbohydrate antigens 12-5 (CA125), and carcinoembryonic antigen (CEA).In conclusion, measurement of serum MIC-1 levels could be considered as a diagnostic biomarker for malignant SPN patients.