How can genetic tumor markers help patients with colorectal cancer?
One example of the value of genetic tumor markers involves the KRAS gene, EGFR, and drug treatments for colorectal cancer called EGFR inhibitors. Recently, researchers have reported that the presence or absence of a mutated copy of the KRAS in colorectal cancer cells makes a difference in whether patients will respond well to an EGFR inhibitor. Studies show that patients who have colorectal tumors without the mutated version of the KRAS gene are much more likely to respond to drugs such as Vectibix™ (panitumumab) or Erbitux® (cetuximab), which are two EGFR inhibitors. This makes it possible to use KRAS as a marker for the ability to respond to treatment with EGFR inhibitors. Since most effective treatments for cancer have serious side effects and are expensive, it is important for a person with colorectal cancer to know as early as possible whether a particular treatment may be useful or not. The National Cancer Institute (NCI) database currently lists more than 100 ongoing clinical re
