BACKGROUND: Our study was designed to improve the accuracy of determining whether pulmonary nodules are benign or malignant. METHODS We evaluated the clinical and imaging features and serum markers: neuron specific enolase (NSE), carcino-embryonic antigen (CEA), cytokeratin fragment antigen 21-1 (CYFRA 21-1), miRNA-21-5p, and miR-574-5pof in 39 patients with pathology information. Factors ...