Targeted Treatments for Colorectal Cancer

Targeted treatments are new therapies that affect cancer cells, but do little damage to noncancer cells. These drugs are becoming more important in the treatment of colorectal cancer. These treatments are sometimes known as immunotherapies because they help the patient’s immune system fight cancer more effectively.

• Antiangiogenesis therapy - Tumors need the nutrients in blood vessels to grow and spread. Antiangiogenesis therapies stop the process of making new blood vessels, known as angiogenesis, by “starving” the tumor. Avastin^® (bevacizumab) is one of these therapies, and it works by blocking the growth factors that stimulate the development of new blood vessels. Bevacuzimab is given with chemotherapy to improve survival in people with advanced colorectal cancer.
• Epidermal growth factor receptor (EGFR) inhibitors - The EGFR protein seems to help many colorectal cancers grow. Erbitux^® (cetuximab) is a monoclonal antibody, or protein used by the immune system, that can find and attach itself to cancer cells and can block the EGFR protein. Cetuximab can sometimes shrink tumors in patients whose cancers continue to grow after other treatments. Cetuximab can be used with or without irinotecan. Vectibix^TM (panitumumab), another monoclonal antibody, is a newer EGFR inhibitor that can shrink tumors in some people whose cancer has not responded to other treatments. Vectibix is used to treat certain colorectal cancers that have metastasized (spread to other parts of the body) and continue to grow after treatment with combinations of chemotherapy drugs that include 5-FU, oxaliplatin, or irinotecan. Recent studies have shown that genetic testing is required on the tumor tissue to determine whether EGFR inhibitors will be a useful treatment prior to the use of these drugs. This should be discussed with your physician.