Biomarkers are biological molecules found in blood, other body fluids, or tissues that can be a sign of a normal or abnormal process, or of a condition or disease. In cancer, biomarkers can provide important information about the likely course of the disease and how it may respond to treatment. By identifying specific biomarkers, doctors can select the most appropriate and effective therapies for each patient. For example, the presence of the HER2 protein in breast cancer can indicate that a patient may benefit from HER2-targeted therapies like trastuzumab.
