[The role of tumor markers in lung cancer management]

A variety of substances, including enzymes, hormones, antigens and proteins are called tumor markers. In this report, tumor marker of lung cancer refers to substances in serum of patients with lung cancer. In order to evaluate usefulness of tumor markers in lung cancer management, contributory tumor markers to diagnosis of lung cancer were selected by the incidence of elevation. Consequently CEA, SCC, SSEA-1, CA15-3 and NSE were considered to be possibly useful for diagnosis and also classification of histological types of lung cancer. Then the following areas were examined for these markers: (1) usefulness for making a decision of therapeutic strategy, (2) predictability for drug and radiosensitivity, (3) judgment of therapeutic effect; and (4) value in monitoring clinical course. From these analyses some positive data for tumor markers to be useful in lung cancer management were obtained as follows. Since serum values exceeding 10 ng/ml for NSE were observed mostly in advanced stage of small cell lung cancer, intensive chemotherapy should be carried out in such cases. But inoperability of non-small cell lung cancer could hardly be predicted by elevation of tumor markers. No correlation was proved between expression of any tumor markers to be available in today's clinical practice and therapeutic sensitivity. Response to treatments could be evaluated by serial measurements of serum level although definite criteria for judgment have not been determined. Periodic surveys of tumor markers expressed in lung cancer were predictable for relapse prior to imaging detection. Tumor markers of lung cancer take an important role in lung cancer management.