The AUC of serum mesothelin to distinguish patients with mesothelioma from those with metastatic cancers to pleura was significantly higher than that of serum midkine (p = 0.0330) but was not different from that of combination of both mesothelin and midkine (p = 0.0738) (Fig. 2a). The gene discussed is MDK; the disease is metastatic malignant neoplasm.