Evaluation of serum and pleural levels tumor M2-pyruvate kinase in lung cancer patients with pleural effusion

Objective To evaluate the diagnostic value of tumor M2-pyruvate kinase (TuM2-PK) and carcinoembryonic antigen (CEA) levels in both pleural effusion and serum in the differential diagnosis of benign and malignant pleural effusion. Methods This prospective study was conducted among 80 patients with benign pleural effusion (BPE group) and 125 patients with malignant pleural effusion associated with lung cancer (MPE group). The levels of TuM2-PK and CEA were measured by using sandwich enzyme-linked immunosorbent assay and electrochemiluminescence. The receiver-operating characteristic curve (ROC) analysis was used to confirm the cutoff value to evaluate the diagnostic efficiency of TuM2-PK and CEA. Results The TuM2-PK and CEA levels in pleural effusion and serum, and their ratio (P/S) were higher in MPE group than that in BPE group ( P < 0.05). In pleural effusion and serum, the diagnostic efficiency of combined TuM2-PK and CEA for MPE was superior to either single detection. Conclusions The combined detection of TuM2-PK and CEA has a high sensitivity for diagnosis of MPE and might provide method for rapid and accurate diagnosis of patients.