Tumor M2-pyruvate kinase in lung cancer patients: immunohistochemical detection and disease monitoring.

Lung cancer is one of the main causes for cancer death. A reliable diagnosis and follow-up of patients is important support for a successful therapy. The diagnostic efficiency of a new marker Tumor M2-pyruvate kinase (Tumor M2-PK) is evaluated. In this report immunohistochemical detection of pyruvate kinase M2 in tissue sections of lung cancer specimens is presented. Furthermore Tumor M2-PK was quantified in EDTA plasma of lung cancer patients in order to monitor the disease, especially under chemotherapy. Immunohistochemical detection of pyruvate kinase M2 in tissue sections of lung cancer specimens showed selective staining of tumor cells, independent of the histological classification of the tumor. In EDTA plasma of lung cancer patients, the marker concentrations correlated well with the tumor load during follow-up, showing significantly increasing concentrations with progressive tumor stages and decreased concentrations during tumor remission. Again, this effect was independent of the histological tumor type. The present data indicate that Tumor M2-PK in EDTA-plasma could be a valuable tumor marker for monitoring lung cancer.