Finding the treatment that fits your needs and most effectively fights your colorectal cancer is likely your top priority after diagnosis. It’s ours, too. Surgery is often used to remove cancerous polyps and tumors, but other options — such as systemic therapies and radiation— are sometimes necessary in order to shrink the tumor prior to surgery. In addition, systemic therapy may be necessary after surgery to prevent cancer recurrence or to treat cancer that has spread to other areas of the body.
Systemic therapies focus on changing or destroying cells within your body in order to fight the cancer and keep it from spreading. Cancer lives within the cells of your body. In order to fight colorectal cancer, you need to destroy those cancer cells.
Systemic therapies, which include chemotherapy, targeted therapy, and immunotherapy, are often used:
- Before and/or after surgery for colorectal cancer that
- Has spread outside of the colon/rectum to nearby tissue/organs or lymph nodes (also called locally advanced cancer),
- Has invaded through the wall of the colon or rectum
- In patients who have been diagnosed after the cancer has spread to further parts of the body (also called metastatic cancer)
Types of Systemic Therapies for Colorectal Cancer
There are several kinds of systemic therapies for colorectal cancer. At Fox Chase, we primarily use:
- Chemotherapy, which uses medicine to destroy, stop the spread of, or slow the growth of cancer cells
- Targeted therapy, which uses medicine to block the growth and spread of cancer by targeting specific molecules that help the cancer spread
- Immunotherapy, which uses your own immune system to recognize and destroy cancer cells
Fox Chase’s Approach to Systemic Therapies for Colorectal Cancer
At Fox Chase, we emphasize developing a treatment that’s tailor-made for you. Your care team will consist of many specialists — like your medical oncologist, oncology nurses, and social workers — who will discuss your progress and make changes to your treatment approach as needed.
A Closer Look: Chemotherapy
Chemotherapy is often used to treat colorectal cancer — either alone or alongside other treatments. It can be used after surgery to destroy any cancer cells that might remain. Or it can be given before surgery in order to try to shrink the cancer, making it easier to remove. It can also be used for advanced cancers that have spread to other organs in order to help shrink those tumors and ease your symptoms.
How does chemotherapy work?
Chemotherapy is a way to kill the colorectal cancer cells in your body. The medicine enters the bloodstream to reach all parts of your body to destroy cells that are dividing quickly, which is why it works against cancer cells.
What happens during chemotherapy?
In systemic chemotherapy, the medicine is either administered directly into your veins through an IV or taken by mouth. Chemotherapy is given in cycles. After each treatment, you’ll be given a rest period to allow your body to recover. These rest periods can last anywhere from 1 to 4 weeks. Most patients will go through several cycles of chemotherapy for colorectal cancer.
Chemotherapy can be used alone or along with other therapies, depending on your needs.
What are the possible side effects of chemotherapy?
Chemotherapy attacks cells that are rapidly dividing, so it can also destroy other cells — like bone marrow, the lining of the intestines and mouth, and hair follicles — at the same time.
Common side effects of chemotherapy include:
- Hair loss or thinning
- Mouth sores
- Loss or change of appetite
- Nausea and vomiting
- Increased risk of infection (due to fewer white blood cells)
- Bruising or bleeding easily (due to fewer blood platelets)
A Closer Look: Targeted Therapy
Targeted therapy only works for some kinds of cancers — and colorectal cancer is one of them. It requires the tumor to have an appropriate “target” for the medicine to find and treat, often in the form of a specific gene mutation or protein expression. If your tumor has a target that works for targeted therapy, targeted therapy may be an option for you.
How does targeted therapy work?
Targeted therapy for colorectal cancer targets specific molecules — called molecular targets. Where chemotherapy acts on rapidly dividing cells, targeted therapies are designed to only interact with their target.
One type of targeted therapy works to stop the specific protein that helps blood vessels form in the tumor. This prevents the tumor from growing. Another type of targeted therapy targets a specific protein that is found on the surface of cancer cells that help the tumor grow.
What happens during targeted therapy?
Targeted therapy for colorectal cancer can be used alongside chemotherapy or alone if chemotherapy is no longer working. The medicine is administered through infusions using an IV directly into your veins. This is usually done every couple of weeks. There are some targeted therapies that are taken in pill form, as well.
What are the possible side effects of targeted therapy?
Because they focus on specific cells, targeted therapies can have different — and often fewer — side effects than chemotherapy. Common side effects include:
- Skin problems, such as rashes, dry skin, and hair lightening
- Problems with blood clotting and wound healing
- High blood pressure
A Closer Look: Immunotherapy
Immunotherapy is usually used for patients with advanced colorectal cancer who have a specific type of colorectal cancer called microsatellite unstable. It’s often used when the cancer is still growing after undergoing other treatments, like chemotherapy. It can also be used when the cancer can’t be removed surgically or has spread to other parts of the body, typically after at least one prior treatment using chemotherapy.
How does immunotherapy work?
Immunotherapy for colorectal cancer works by using parts of your body’s own immune system to fight the cancer. This can be done by stimulating your immune system to push it to work harder and attack the cancer cells.
What happens during immunotherapy?
Immunotherapy is given through an IV in order to direct the medicine into your bloodstream. This is often done every couple weeks.
What are the possible side effects of immunotherapy?
The purpose of immunotherapy is to boost the immune system, which can also cause your body to fight off healthy parts of the body. Common side effects include:
- Decreased appetite
- Skin rash
- Joint pain
Sometimes, it can cause your body to attack parts of major organs, which can lead to serious problems, like changes in organ function. In this case, immunotherapy would need to be stopped immediately, and you may need to take high doses of corticosteroids to suppress your immune system.
Coping With Side Effects of Systemic Therapies
Systemic therapies each have their own potential side effects. Many of these side effects can be solved with medication. It’s important you tell your physician how you’re feeling. You should immediately inform your care team if you experience any of the following:
- A fever over 100.4℉
- Severe fatigue
- Nausea that prohibits you from eating
- Vomiting more than 6 times in one day
- Painful mouth ulcers that prohibit you from eating
You also help avoid some side effects by sticking to bland foods, eating smaller and more frequent meals, drinking lots of water, and staying active to fight fatigue.
How can Fox Chase help?
Fox Chase has teams of highly specialized physicians who do not just read the guidelines for treatments, but are often part of creating those guidelines.
Because of this, we are skilled at choosing the treatments that will be most effective for your colorectal cancer and your life in general. Our teams of combined experts from several specialties are here for you every step of the way.