Targeted therapies are designed to treat only the cancer cells and minimize damage to normal, healthy cells. Cancer treatments that "target" cancer cells may offer the advantage of reduced treatment-related side effects and improved outcomes. Traditional treatments for cancer are chemotherapy and radiation. While these are very effective, they cause significant side effects, have a negative effect on the quality of life, and can be almost intolerable for some patients.
These traditional cancer treatments cannot distinguish between cancer and healthy cells, numerous healthy cells can be destroyed, resulting in side effects that include fatigue, hair loss, and vulnerability to infection. The destructive nature of treatment often leads patients to give up and refuse to have another round, and make things difficult for their caregivers.
However, we are learning more about cancer all the time. With some types of cancer, we know exactly what is causing the disease and thus how to stop it. Enter targeted therapy. Targeted therapy endeavors to kill only the tumor, with minimal effect on the surrounding tissue or the overall system. This results in greater effectiveness and fewer side effects. More and more patients are benefitting from these approaches.
Targeted therapy uses a drug or substance that blocks the growth of cancer. Doctors identify certain biomarkers and target them. Biomarkers are specific molecules that exist only in the tumor's cells and are not present in healthy tissue. They differ significantly from drugs used in chemotherapy; rather than killing the cancer, the goal is to prevent it from growing further. It is part of the foundation of precision medicine and is a type of treatment that typically targets proteins that control how cancer cells grow, divide, and spread.
The choice of targeted therapy depends on the type of tumor, not its location. In the past, lung cancer and breast cancer, for example, have been seen as very different diseases, but targeted therapy changes this. The same treatment might be used for colon and stomach cancer, providing the tumors use the same biomarkers.
The treatment process depends on the specific drug being used. There are two ways targeted drugs are normally given:
Oral cancer drugs should be treated as hazardous and kept well away from children and pets. Before getting targeted therapy, you may need a biopsy to test what drugs the cancer is going to best respond to. There may be other criteria, such as unsuitability for surgery.
Targeted therapies fall into a number of different types, which may act in different ways. Different cancers tend to require a different approach. Here are the seven basic types of targeted therapy:
The overall idea is that the therapy must affect only the cancer cells.
The frequency and length of targeted therapy treatment will depend on your cancer and how well you respond to treatment. Treatment may be every day, every week, or every month. You might also be given the treatment in cycles; a period of treatment followed by a break.
You must follow all of your doctor's instructions and go to all follow-up appointments. Your cancer care team will work with you for your individualized cancer treatment plan.
Targeted therapies have far fewer side effects than traditional chemotherapy or radiation therapy. However, they are not completely free of side effects and problems. Common side effects include:
There may be other side effects with the specific drug you are receiving; check with your oncologist.
You will be seeing a lot of your doctor during the process, and they will assess whether the treatment is working.
Your doctor may order a variety of medical tests, including scans of the tumor and blood tests to help determine whether or not it is working. Doctors will look at measures such as whether the tumor is growing or shrinking and how much genetic material from the tumor is in your blood.
If your oncologist is recommending targeted treatment, you should ask a few questions. Here are some suggestions:
You should make sure you have all of the information you need before agreeing to treatment. This is particularly important if your doctor is suggesting enrollment in a clinical trial (there are clinical trials for new targeted therapies going on all the time).
At Compass Oncology, we are finding many of our patients benefit from targeted therapy. It's a new tool we can use to improve patient outcomes, although it is not suited to everyone. Talk to us to find out more and schedule a consultation with one of our oncologists.