Bio marker is a biological molecule found in blood, other body fluids, or tissues that is a sign of a normal or abnormal process, or of a condition or disease. A bio marker may be used to see how well the body responds to a treatment for a disease or condition.
In cancer research and medicine, bio markers are used in three primary ways:
·To help diagnose conditions, as in the case of identifying early stage cancers (Diagnostic)
·To forecast how aggressive a condition is, as in the case of determining a patient's ability to fare in the absence of treatment (Prognostic)
·To predict how well a patient will respond to treatment (Predictive).