Understanding My Treatment Options
Treatment and Side Effects
After a colon cancer diagnosis, you and your doctors will put together a treatment plan specific to your situation, based on your pathology report and other tests. Your treatment plan will be made up of one or more specific treatments that are intended to target the cancer cells in different ways. Based on your stage of cancer, your plan may include a combination of surgery, chemotherapy, radiation therapy and targeted therapies. Your physician will also recommend a follow-up regimen including exams and tests to monitor for recurrence.
The first step of treatment for most colon cancer patients is surgery. The size and location of the tumor, cancer stage, and your preference all impact the type of surgery recommended.
You may be eligible for a colectomy or a segmental resection, a surgical procedure that removes the tumor, a small piece of normal colon around the tumor and nearby lymph nodes (at least 12). The remaining healthy sections of the colon are reconnected with sutures or staples to maintain a normal passageway for stool. There are two types of colectomies commonly performed:
- Open Colectomy: A long incision is made in the abdomen and surgery is performed through the opening.
- Laparoscopic Colectomy: Several small incisions are made in the abdomen through which a specially designed instrument is inserted to allow the surgeon to see inside and operate within the abdomen. This option is minimally invasive.
In a small percentage of cases doctors may suggest a diverting ostomy, a procedure where a portion of the colon is brought through the abdominal wall to create a passageway for stool. This occurs when the cancer has spread to the lowest portion of the colon or when the tumor blocks the flow of stool through the colon.
Visit Fight Colorectal Cancer for more information about your surgical options.
After your surgery for colon cancer, some of the tumor tissue removed from your body is processed into a tissue block and stored. A number of tests can be conducted using the tissue block to provide more information about your specific cancer to help guide you in making decisions about treatment. Talk to your doctor about diagnostic tumor tests that may be appropriate for you. Depending on the stage of your cancer, your physician may suggest one or more of the following:
- Oncotype DXi: Oncotype DX Colon Recurrence Score is an advanced diagnostic test for patients with Stage II or stage III A/B colon cancer. The test looks at your tumor’s unique biology to help identify the risk that your cancer will return (recur) following surgery. The Oncotype DX test is performed on a small tissue sample taken from your surgery; therefore, no additional procedures are needed to get your test result, known as your Recurrence Score result. The Oncotype DX Colon Recurrence Score has been clinically validated and can provide information to help you and your doctor answer critical questions when selecting your treatment plan.
- Previstage™ii : Previstage GCC Colorectal Cancer Staging test is a molecular test that provides physicians with additional information to help determine the stage of a patient's colon cancer.
- UGT1a1: UGT1a1 is a gene that controls the liver’s ability to metabolize a chemotherapy treatment called irinotecan. About 10% of the general population has a mutation in this gene which results in an inability to completely metabolize the drug. These people may have an increased risk of serious side effects, particularly low white blood cells counts and diarrhea. There is a test for UGT1a1 that can be done before beginning irinotecan. The FDA label for this drug recommends that patients who have this genetic difference begin treatment at a lower dose.
- DPYD/TYMS: Variations in the DYPD (dihydropyrimidine dehydrogenase) and TYMS (thymidylate synthetase) genes may contribute to a higher risk of adverse reactions to the chemotherapy drug 5-fluorouracil (5-FU). Patients who may have long-term exposure to this drug or whose family members have experienced adverse reactions or did not respond to 5-FU should undergo a genetic test to determine if there are mutations in their DYPD and TYMS genes.
- MMR/MSI: MMR (DNA mismatch repair) and MSI (microsatellite instability) testing provides patients and their doctors with additional information about potential prognosis, as well as a hereditary cancer syndrome called Lynch syndrome. About 15% of colon cancer patients have tumors that are MSI-High (MSI-H), meaning they are MMR deficient (MMR-D). Studies have shown that Stage II colon cancer patients with MSI-H/MMR-D tumors have a lower risk of recurrence compared to patients with MMR proficiency. All patients should be assessed for a hereditary cancer syndrome at the time of diagnosis of colon canceriii; approximately 5 – 6% of patients with colon cancer may have Lynch syndrome or another hereditary cancer and should speak with their physician about a formal genetic evaluation.
- KRAS mutation: This test is generally conducted on the tissue of patients with Stage IV or recurrent colon cancer, who may be candidates for EGFR inhibitors targeted therapies including Erbitux®iv (cetuximab) or Vectibix®v (panitumumab). Approximately 35% - 40% of all colorectal cancers contain a mutated KRAS gene; research has shown that patients with a KRAS mutation do not benefit from EGFR targeted therapies. If you have a normal, non-mutated (wild-type) KRAS gene, EGFR inhibitors may be a treatment option for you.
Visit Fight Colorectal Cancer for more information about tests for your colon cancer.
After undergoing surgery for colon cancer, depending on the stage of your colon cancer, your physician may recommend systemic treatment to help prevent the cancer from coming back (recurrence) or to reduce the spread of disease.
- Adjuvant Chemotherapy: Your doctor may recommend adjuvant chemotherapy, which is treatment in addition to surgery, to prevent recurrence. In general, most people with Stage III colon cancer receive chemotherapy, while people with Stage II colon cancer receive chemotherapy only if they are at high risk for recurrence. Chemotherapy kills cancer cells in the whole body by interfering with cell growth and division. Chemotherapy drugs may be given intravenously or orally. There are a number of different types of chemotherapy drugs, which are often given in combination with each other or in succession to maximize the treatment benefit.
Side effects from chemotherapy are common because these treatments affect all rapidly dividing cells, not just abnormal cancer cells. Cells that are most commonly affected are those of the bone marrow, digestive tract, reproductive system, and hair follicles. This is why hair loss and nausea are common side effects of chemotherapy, although the most common chemo for Stage II and Stage III colon cancer does not generally cause hair loss. It is important to note that side effects vary for each chemotherapy drug. If your doctor believes that you are a good candidate for chemotherapy, you should work with your health care team to determine the best chemotherapy regimen for you.
Stage IV or Recurrent
- Pre and/or Post-Operative Chemotherapy: If you have newly diagnosed Stage IV cancer, your doctor may recommend neoadjuvant (pre-surgery) chemotherapy. This can help shrink the tumor and help make surgical removal of the tumor easier. Neoadjuvant chemotherapy is commonly used for colon cancer that has spread to the liver. If you have recurrent cancer (cancer diagnosed at an earlier stage which has come back), your treatment may depend on the treatment you received earlier.
Visit Fight Colorectal Cancer for more information about chemotherapy options.
For patients with Stage IV or recurrent colon cancer, targeted therapies can be used in conjunction with chemotherapy or by themselves if chemotherapy is no longer working. These targeted drugs work differently from standard chemotherapy drugs in that they specifically target the genetic or protein changes in cells that cause cancer.
Targeted therapies for colon cancer include:
- Bevacizumab (Avastin®vi): Bevacizumab is a monoclonal antibody designed to prevent the growth of new blood vessels. Tumors have a protein called vascular endothelial growth factor (VEGF) that helps them form new blood vessels to receive nutrients and grow (a process known as angiogenesis). Bevacizumab targets the VEGF protein, effectively "starving" the tumor.
- Cetuximab (Erbitux®): Cetuximab is a monoclonal antibody that specifically attacks epidermal growth factor receptor (EGFR), a protein that often appears in high amounts on the surface of cancer cells and helps them grow. Patients whose tumors are KRAS wild-type (no mutations) are recommended for this drug.
- Panitumumab (Vectibix®): Panitumumab is another monoclonal antibody that attacks the EGFR protein. Similar to cetuximab, this drug is recommended for patients whose tumors are KRAS wild-type.
Visit Fight Colorectal Cancer for more information about treatment options for Stage IV colon cancer.
The following additional treatments are used in very specific situations, in a small percentage of patients with Stage IV colon cancer.
Radiation therapy: Radiation may be used after surgery to help destroy any remaining cancer cells and to ease symptoms such as blocking of the intestine, internal bleeding, or pain. Radiation can also be used prior to surgery to shrink the tumor if the location or size of a tumor makes it difficult to surgically remove.
Ablation: Cancer that has spread beyond the colon may be treated with radiofrequency ablation, using high-intensity, focused radio waves to destroy the tumor tissue. Potential side effects after ablation therapy include abdominal pain, infection, or bleeding.
Palliative care: Your doctor may also recommend palliative care or therapy to relieve the symptoms of cancer or reduce the spread of disease. The goal of palliative therapy is to lengthen and improve quality of life, slow the spread of cancer, and relieve pain from cancer that has spread. Visit the Fight Colorectal Cancer website for more information about palliative care.
Building a Treatment Plan
Depending on the stage of your colon cancer, your treatment may include one or more of the treatment options mentioned above. Your physician will also recommend a follow-up regimen including exams and tests to watch for recurrence. It’s important to understand your specific colon cancer diagnosis as you and your doctor develop a treatment plan.
No two diagnoses and treatment regimens for colon cancer look exactly the same, which is why learning all you can about your options and talking to your health care team are critical. Empower yourself with personalized information about your type of cancer by answering a few simple questions in the My Colon Cancer Coach questionnaire. You’ll receive a customized report to help you better understand your cancer, and can use the report to discuss next steps with your doctor.
Your Personalized Treatment Guide
i. Oncotype DX is a registered trademark of Genomic Health Inc.
ii. Previstage™ is a registered trademark of DiagnoCure
iii. ASCO Institute for Quality
ivi. Erbitux® is a registered trademark of Eli Lilly and Company
v. Vectibix® is a registered trademark of Amgen Inc.
vi. Avastin® is a registered trademark of Genentech, Inc.