Clinical value of jointly detection pleural fluid Midkine, pleural fluid adenosine deaminase, and pleural fluid carbohydrate antigen 125 in the identification of nonsmall cell lung cancer-associated malignant pleural effusion.

Midkine (MK) level has been shown to be elevated in serum of patients with nonsmall cell lung cancer (NSCLC). However, the diagnostic value of MK in pleural effusion in NSCLC has not been well validated and established. Samples of NSCLC-associated malignant pleural effusions (MPE) and benign effusions (BPE) were collected. The pleural fluid MK (pMK), pleural fluid adenosine deaminase (pADA), pleural fluid lactate dehydrogenase (pLDH), pleural fluid glucose (pGLU), pleural fluid ferritin (pFER), pleural fluid CA199 (pCA199), pleural fluid CA125 (pCA125), pleural effusion white cell count (pWBC), and pleural effusion red cell count (pRBC) were analyzed, and the clinical data of each group were collected for statistical analysis. The level of pMK, pCA125, pMK + pCA125, and pMK + pCA125 + pADA in the MPE was significantly higher than the BPE group (P = .003, .000, .000, .000). The pADA level in the BPE was significantly higher than the MPE group (P = .003). It showed that the area under the ROC curve (AUC) (0.816) of jointly detection pMK, pCA125, and pADA was significantly higher than other markers for the diagnosis of MPE. Therefore, joint detection of pMK + pCA125 + pADA suggested that the sensitivity, specificity, and AUC was 82.54%, 74.19% at the cutoff 0.47 and diagnostic performance was higher than others. Joint detection of pMK + pCA125 + pADA can be used as a good indicator for the identification of MPE of NSCLC.