The human body is made of millions of cells – each doing its part to make sure we are healthy and strong. However, a mutation is a change in the gene that can happen to a cell at any time.
Cancer starts when certain genes in healthy cells change. Things that we are exposed to in our environment, including cigarette smoke, radiation, hormones and diet, can cause some acquired mutations. However, other mutations have no clear cause and seem to occur randomly as the cells divide.
“Normal cells stop growing or reproducing when enough cells are present, but cancer cells don’t stop growing,” said Dr. Demet Gokalp Yasar, medical oncologist/hematologist with Marshfield Clinic Health System.
Traditionally, your oncologist would use chemotherapy to kill the cancer cells along with many of the other cells in your body. Targeted cancer therapies on the other hand are drugs that target the mutant abnormal cells (cancer cells), but do not affect the activity of the normal cells.
How it works
Targeted cancer therapies are drugs that block the growth and spread of cancer. The drugs interfere with specific molecules (molecular targets) that growth and spread the cancer.
Many targeted cancer therapies have been approved by the Food and Drug Administration (FDA) to treat specific types of cancer. In addition, others are being studied in clinical trials. Oncologists can use targeted therapies to treat many types of cancer including carcinomas, sarcomas, melanomas, lymphomas and leukemia.
“This treatment option is very promising and researchers are studying many new targets and drugs every day,” said Dr. Yasar.
Two types of targeted therapies
One type of targeted therapy uses small molecules that can block the process that helps cancer cells multiply and spread. You can usually take these drugs as pills.
The other type of targeted therapy is a Monoclonal antibody that blocks a specific target on the outside of cancer cells and/or the target might be in the area around the cancer. Your oncologist will typically inject these drugs into a vein, or intravenously (IV). Targeted therapy offers your oncologists a better way to customize cancer treatment.
Advantages of targeted therapy include:
- Potentially less harm to normal cells.
- Potentially fewer side effects.
- Improved effectiveness.
- Improved quality of life.
Targeted therapies may have some disadvantages such as:
- Cancer cells can become resistant to them.
- Drugs for some targets are hard to develop.
Targeted therapy, much like other drugs, can cause side effects. The type of targeted therapy you receive and how your body reacts to the therapy can cause different side effects. There are also medicines for many of these side effects. These medicines may prevent the side effects from happening or treat them once they occur. Most side effects of targeted therapy go away after the treatment ends.
Your oncologist will order your tumor to be tested to see if it contains targets for which there are targeted therapies. To have your tumor tested for targets, you may need to have a biopsy or blood draw. Your oncologist will use this to determine the best treatment option.
For more information about targeted therapies, talk to your oncologist.