[Tumor markers--how they should be applied]

Determination of a tumor marker is currently not suitable method for screening purpose (exception: PSA and thyroglobulin). Tumor marker determination cannot be employed to exclude the presence of a tumor. Prior to surgery, however, such determination is desirable, and in the case of germ cell tumors even mandatory. Postoperatively, or after termination of adjuvant chemotherapy and/or radiotherapy, determination of tumor markers as an individual baseline is necessary for the further disease course. During the course of the disease and for follow-up care, the kinetic development of tumor factors is, in comparison with the individual baseline values, of decisive importance. However, in order to ensue correct interpretation it is important to use the same test system.