(rÄâ²dÃ¤r) 1. A method of detecting distant objects and determining their position, speed, or other characteristics by causing radio waves to be reflected from them and analyzing the reflected waves. The waves can be converted into images, as for use on weather maps.
A high level of the marker may indicate a worsened prognosis in some situations. The most effective and common purpose of tumor markers is to monitor the cancer treatment. As the cancer levels go on decreasing in the body, the marker also goes down. If the marker remains stagnant or increases, it is usually an indication that the patient is not responding sufficiently to the treatment.
Tumor markers are chemicals made by tumor cells that can be detected in your blood. But tumor markers are also produced by some normal cells in your body, and levels may be significantly elevated in noncancerous conditions. This limits the potential for tumor marker tests to help in diagnosing cancer.