CONDITIONS

Colon and Rectal Cancer

What Is Colon and Rectal Cancer

Colon cancer is the third most commonly diagnosed cancer in the United States, and is the second leading cause of cancer death in both men and women. The American Cancer Society estimates that close to 140,000 will be diagnosed this year with colorectal cancer, and that more than third—about 50,000—will die from it.

Colon cancer is cancer of the large intestine, or colon, which is the lower part of the digestive system. Rectal cancer is cancer of the last several inches of the colon, or rectum. Together, they’re often referred to as colorectal cancers.

Most cases of colon cancer begin as small, noncancerous, or benign, clumps of cells that are called adenomatous polyps. Some of these polyps, however, develop into cancer over time. Polyps may be small and produce few, if any, symptoms. For this reason, doctors recommend regular screening tests to help prevent colon cancer by identifying polyps before they become colon cancer.


There are several types of cancer that can start in the colon or rectum.

  • Adenocarcinomas: This is the most common type of colorectal cancer—with 95% of all colorectal cancers are adenocarcinomas—and is generally what doctors are referring to when they speak about colorectal cancer.

As well, there are other, less common types of tumors, which may also begin in the colon and rectum. Among them:

  • Carcinoid tumors: Specialized hormone-producing cells in the intestine can sometimes become cancerous tumors.
  • Gastrointestinal stromal tumors (GISTs):  Specialized cells in the wall of the colon called the interstitial cells of Cajal can become cancerous; while some are benign others are malignant. These tumors are usually found anywhere in the digestive tract, and are unusual in the colon, though they do occur.
  • Lymphomas: Cells that typically start in lymph nodes can form into lymphomas, a cancer of the immune system that can start in the colon, rectum, or other organs.
  • Sarcomas: This rare type of cancer of the colon or rectum can start in blood vessels, as well as in muscle and connective tissue in the wall of the colon and rectum.

 

What Causes Colon and Rectal Cancer

In most cases, it’s not clear what causes colon cancer—though there are a number of risk factors that increase the chance of developing colorectal cancer.

Risk Factors For Colon and Rectal Cancer

Researchers have found several risk factors that may increase a person’s chance of developing colorectal polyps or colorectal cancer.


Lifestyle-related factors:

  • A high-fat, low fiber diet. Colon cancer and rectal cancer is associated with a diet low in fiber and high in fat and calories. Studies have found an increased risk of colon cancer in people who eat diets high in red meat (beef, pork, lamb, or liver) and processed meats (hot dogs and some luncheon meats). Cooking meats at very high temperatures (frying, broiling, or grilling) creates chemicals that might increase cancer risk, but it’s not clear how much this might contribute to an increase in colorectal cancer risk. In contrast, diets high in vegetables, fruits, and whole grains have been linked with a decreased risk of colorectal cancer,
  • A sedentary lifestyle. If you’re not physically active, you have a higher chance of developing colon cancer. Getting regular physical activity, however, may considerably reduce your risk of colon cancer.
  • Obesity. Being very overweight substantially increases risk of developing colorectal cancer, and also increases risk of dying from it than if you were normal weight. While obesity raises risk for both men and women, the link seems to be stronger in men.
  • Smoking. Long-term smokers are more likely to develop and die from colorectal cancer. People who smoke cigarettes may have an increased risk of colon cancer—quitting can help reverse this risk factor.
  • Heavy alcohol use. Heavy use of alcohol is linked to higher risk of colon cancer.

Other risk factors include:

  • Diabetes. People with diabetes and insulin resistance may have an increased risk of colon cancer.
  • Age. The chances of developing colorectal cancer increase markedly after 50—in fact, 9 out of 10 people diagnosed with this type of cancer was at least 50 years old at time of diagnosis. Colon cancer can occur in younger people, but it occurs much less frequently.
  • Race. African-Americans have the highest risk of colon cancer incidence and mortality all groups in the USA, while Jews of Eastern European decent have one of the highest colorectal cancer risks of any ethnic group in the world. The reasons for this are not yet fully understood, though some gene mutations have been identified as major risk factors, like I1307K APC mutation, is present in about 6% of American Jews
  • A personal history of colorectal cancer or polyps. If you’ve already had colon cancer or adenomatous polyps, you have a greater risk of colon cancer in the future.
  • Inflammatory intestinal conditions. Chronic inflammatory diseases of the colon, like ulcerative colitis and Crohn’s disease, can increase risk of colon cancer. If you have one of these conditions, you have an increased risk of developing colorectal cancer and may need to start screening for colorectal cancer at an earlier age, and be screened more often.
  • Inherited syndromes that increase colon cancer risk. About 5% to 10% of people who develop colorectal cancer have inherited gene syndromes that are hereditary, which that can impact risk significantly. These syndromes include familial adenomatous polyposis and hereditary nonpolyposis colorectal cancer, which is also known as Lynch syndrome. If you have a family history of colorectal cancer, talk to your doctor about starting screening at a younger age.
  • Family history of colon cancer and colon polyps. Colon cancer can run in families—you are more likely to develop colon cancer if you have a parent, sibling or child with the disease. If more than one family member has colon cancer or rectal cancer, your risk is even greater. In some cases, this connection may not be hereditary or genetic. Instead, cancers within the same family may result from shared exposure to an environmental carcinogen or from diet or lifestyle factors.
  • Radiation therapy for cancer. Having undergone radiation therapy to treat previous cancers, particularly if it was directed at the abdomen to treat previous cancers, can increase risk of developing colon cancer.

Diagnosing Colon and Rectal Cancer

In addition to a physical exam, your doctor will ask about your medical and family history, and will then perform diagnostic tests to determine if you have colorectal cancer. Here are the most common tests used to screen for and diagnose colorectal cancer:

  • Colonoscopy. A colonoscope—a long flexible, lighted tube that has a tiny camera attached to the end is inserted into the rectum and gives your doctor the ability to look inside the entire color and rectum, while a patient is sedated. This allows for careful inspection of the internal lining of the colon for polyps and other abnormalities. If something suspect is found, the doctor may perform a biopsy to collect tissue samples for further testing for colorectal cancer
  • Biopsy. A biopsy is the removal of a small amount of tissue to be analyzed for signs of cancer. Other tests can suggest that cancer is present, but only a biopsy can make a definitive diagnosis of colorectal cancer. A biopsy may be performed during a colonoscopy, or it may be done on any tissue that is removed during surgery.
  • Polypectomy (via colonoscopy): During a colonoscopy, your gastroenterologist uses a colonoscope to perform this procedure, which involves removing small polyps from the colon or rectum. The polyps are then analyzed in a laboratory to check for cancer.
  • Barium enema: This test is used to take X-rays of the large intestine, which includes the colon and rectum; and helps your doctor stage colorectal cancer. In some cases, it is used when a colonoscopy is not an option. For the test, your doctor delivers an enema containing barium through a thin tube that is inserted through the rectum. The solution travels through the rectum and colon, coating the organs. After the solution has been given, air is released through the tube to help the colon expand and make it easier for your doctor to see abnormal growths. A series of X-rays are then taken to reveal images of the colon and rectum. These can enable your doctor to detect polyps and other suspicious tissues, which need to be looked at more closely or removed in a colonoscopy.
  • Stool test. Having a yearly fecal test, which look for invisible blood in the stool, an early sign of colon cancer, can be a great detection—and non-invasive—tool for colon cancer diagnosis.
  • Blood Tests. Because colorectal cancer often bleeds into the large intestine or rectum, people with the disease may become anemic. A test of the number of red cells in the blood, which is part of a complete blood count (CBC), can indicate that bleeding may be occurring. Another blood test detects the levels of a protein called carcinoembryonic antigen or CEA. High levels of CEA may indicate that a cancer has spread to other parts of the body.
  • CT or CAT scan. A computer tomography, or CT scan creates a three-dimensional picture of the inside of the body via use of an x-ray machine. A computer combines the images into a detailed, cross-sectional view that shows any abnormalities or tumors. A CT scan can also be used to measure the tumor’s size.
  • MRI (magnetic resonance imaging). An MRI uses magnetic fields, not x-rays, to produce detailed images of the body. MRI can also be used to measure the tumor’s size. MRI is the best imaging test to find where the colorectal cancer has grown.
  • Endoscopic ultrasound or EUS. This test uses sound waves to create a picture of the internal organs. This test can help your doctor stage the cancer, and also help find out if the cancer has spread. Ultrasound, however, cannot accurately detect cancer that has spread to nearby lymph nodes or beyond the pelvis.
  • Chest x-ray. An x-ray might be sued to see if the cancer has spread to the lungs.

After diagnostic tests are done, your doctor will review all of the results with you and discuss next steps if applicable.

Symptoms of Colon and Rectal Cancer

Many people with colon cancer experience no symptoms in the early stages of the disease. When symptoms appear, they’ll likely vary, depending on the cancer’s size and location in your large intestine. This is why screening is so important.

Here are some signs and symptoms of colon cancer to watch out for:

  • Change in your bowel habits, such as diarrhea, constipation, or change in the consistency of your stool
  • Rectal bleeding or blood in your stool
  • Persistent abdominal discomfort, such as cramps, gas, or unexplained pain or discomfort
  • A feeling that your bowel doesn’t empty completely
  • Weakness or fatigue
  • Unexplained weight loss

If you notice any symptoms of colon cancer, such as blood in your stool or a persistent change in bowel habits, make an appointment with your doctor.

Talk to your doctor about when you should begin screening for colon cancer. Guidelines generally recommend colon cancer screenings begin at age 50. Your doctor may recommend more frequent or earlier screening if you have other risk factors, such as a family history of the disease.

 

Prognosis

The outlook for people with colon cancer is better than ever before, thanks to early detection and improvements in understanding and treatment. There are 1 million colon cancer survivors alive in the USA. But colon cancer can still be lethal if it’s not caught early.

Colon cancer death rates have been dropping since the mid-1980’s in part due to increased awareness and increased rates of screening. Finding polyps and cancer in the early stages (local and regional) is when colorectal cancer is easiest to treat.

      Local Stage: The five-year survival rate is 90%

      Regional Stage: The five-year survival rate is 70%

      Distant Stage: The five-year survival rate is 12%

Living With Colon and Rectal Cancer

Generally, the goal in colon cancer treatment is to eradicate the cancer, but the disease and its treatments can impact your life. For instance, radiation and chemotherapy may cause nausea, fatigue, or other problems, and surgical treatments can affect your body image. It helps a great deal to talk openly with family, friends, and other colon cancer survivors. There are also medicines available to help with nausea and fatigue, and you can have reconstructive surgery after a mastectomy to help you feel better about your body.

After colon cancer treatment, you should follow up with checkups every 3 to 6 months to make sure the cancer has not returned.

Screening

Early detection is key to surviving colon cancer. With regular screening, color cancer can be found and treated early, when treatment is most effective. In many cases, screening can actually prevent colon cancer by finding and removing polyps before they become cancerous. The most important point about screening for colon cancer is this: If cancer is found, the earlier the detection, the higher the rate of survival.

  • Over 90% of those diagnosed when cancer is found at local stage—meaning the cancer is confined to the colon or rectum—survive ore than 5 years
  • Once cancer is diagnosed at a regional stage—meaning it has spread to surrounding tissues—survival rate drops to 70%
  • When cancer has metastised or spread to more distant areas, only 13% will reach the 5-year survival mark

Screening for colon cancer can include minor surgical removal of polyps, which is why it is so critical to be screened regularly. Finding and removing polyps before they become cancerous is the best way to prevent colon cancer.

These are the most common diagnostic test used to screen and diagnose for colon cancer:

  • Colonoscopy. A colonoscope—along flexible, lighted tube that has a tiny camera attached to the end is inserted into the rectum and gives your doctor the ability to look inside the entire color and rectum, while a patient is sedated. This allows for careful inspection of the internal lining of the colon for polyps and other abnormalities. If something suspect is found, the doctor may perform a biopsy to collect tissue samples for further testing for colorectal cancer
  • Biopsy. A biopsy is the removal of a small amount of tissue to be analyzed for signs of cancer. Other tests can suggest that cancer is present, but only a biopsy can make a definitive diagnosis of colorectal cancer. A biopsy may be performed during a colonoscopy, or it may be done on any tissue that is removed during surgery.
  • Polypectomy (via colonoscopy): During a colonoscopy, your gastroenterologist uses a colonoscope to perform this procedure, which involves removing small polyps from the colon or rectum. The polyps are then analyzed in a laboratory to check for cancer.
  • Barium enema: This test is used to take X-rays of the large intestine, which includes the colon and rectum. It can help your doctor stage colorectal cancer. In some cases, it is used when a colonoscopy is not an option. For the test, your doctor delivers an enema containing barium through a thin tube that is inserted through the rectum. The solution travels through the rectum and colon, coating the organs. After the solution has been given, air is released through the tube to help the colon expand and make it easier for your doctor to see abnormal growths. A series of X-rays are then taken to reveal images of the colon and rectum. These can enable your doctor to detect polyps and other suspicious tissues, which need to be looked at more closely or removed in a colonoscopy.
  • Stool test. Having yearly fecal test, which look for invisible blood in the stool, an early sign of colon cancer, can be a great detection—and non-invasive—tool for colon cancer diagnosis.
  • Blood Tests. Because colorectal cancer often bleeds into the large intestine or rectum, people with the disease may become anemic. A test of the number of red cells in the blood, which is part of a complete blood count (CBC), can indicate that bleeding may be occurring. Another blood test detects the levels of a protein called carcinoembryonic antigen or CEA. High levels of CEA may indicate that a cancer has spread to other parts of the body.

Prevention

There is no sure way to prevent colon cancer, but there are things you can do to reduce your risk:

  • Stay active. Lack of exercise is a risk factor for colon cancer, along with other types of cancer and heart disease. Even moderate exercise can cut your risk of colon cancer. Just fifteen minutes to half an hour of moderate exercise, five days a week, can cut your risk by 18%
  • Smoking cigarettes contribute to risk of colon cancer—quitting is the best thing you can do for your health.
  • If you drink, do so in moderation. Even two to five drinks a day can raise your risk by as much as half.
  • Watch out for hormone treatments. Hormones used for birth control or to treat menopause symptoms may increase your colon cancer risk. If you need contraception or hormone replacement, talk to your doctor about the safest approach.
  • Watch your weight. Obesity increases colon cancer risk, and is a condition that you can work to prevent.

If you are at especially high risk because of genetics or family history, you may also consider strategies such as preventive surgery or estrogen-blocking medications.

Medication And Treatment

Cancer treatment usually involves a team of experts—and with colorectal cancer, you will likely receive care from one or more of the following medical specialists:

  • Gastroenterologist
  • Surgeon
  • Medical oncologist
  • Radiation oncologist
  • Mental health counselors
  • Dietitians
  • Social workers

If you have received a diagnosis of colorectal cancer, the next step is to determine the best course of treatment for your disease. Your doctor will discuss your options for treatment, and will adise on the most optimal course of action to take. The following treatments will likely be discussed, either alone or in combination:

  • Surgery
  • Chemotherapy
  • Radiation
  • Biologic Therapy

Surgical options for colorectal cancer typically depends on how far advanced the cancer is—the invasiveness of the surgical procedure can span from the removal of small tumors while having a colonoscopy to having a section of the colon or rectum removed. If the cancer has metastasized, or spread to other parts of the body, then surgery may be done to remove whatever cancer can be excised from these other areas outside the colon and rectum.   Here are some of the most common types of surgery done to treat this type of cancer:

  • Local excision.  If the cancer is found at a very early stage, your doctor may be able to remove it via use of a colonscope, without having to cut through the abdominal wall.. If the cancer is found in a polyp (a small bulging piece of tissue), the operation is called a polypectomy
  • Bowel resection.  If the cancer cannot be removed via local excisiton, then a bowel resection may be done. In this type of surgery, the cancer in either the color on rectum is cut out, along with adjacent portions of the colon or rectum—this is known as a partial colectomy. The two “healthy” ends of the colon or rectum are then joined together to re-form the tube-shaped organ. Adjacent lymph nodes near the colon may also be removed and examined for signs of cancer.
  • Resection and colostomy.  If too much of the colon needs to be removed, and the two ends are not able to be sewn back together, an opening, or stoma, is made outside the body to allow for waste to pass through. This is known as a colostomy—a bag is placed around the opening to collect the waste, and special care needs to be taken to properly learn how to change and care for the colostomy. Sometimes, the colostomy is not permanent, and is needed only until the ends of the colon have healed sufficiently to reattach. However, if the entire lower colon is removed the colostomy may be permanent.

Other forms of surgery include:

  • Radiofrequency ablation. A special probe that contains tiny electrodes is insterted directly through the skin, which sends impulses that kill cancer cells.  Usually only local anesthesia is needed, but in other cases, the probe may need to be inserted through an incision in the abdomen, and with this type of procedure, general anesthesia is required.
  • Microwave ablation.  Using heat generated by microwaves, microwave ablation destroys tumors that have metastiszide to the liver with microwave energy.
  • Cryosurgery or Cryotherapy.  An instrument is used to freeze and destroy abnormal tissue, usually in the early stages of colorectal cancer.

Adjuvant therapy

Patients are often given chemotherapy or radiation treatement, even if all signs of cancer are cut out at time of surgery to ensure that all cancer cells which might possibly be left do not have the opportunity to peoliferate and create new cancerous growths. This treatment, post-surgery, is known as adjuvant therapy.


Chemotherapy

Chemotherapy is a drug-based cancer treatment intended to stop the growth of cancer cells by killing the cells or by stopping the cells ability to divide and proliferate. The way chemo is given depends on the stage and type of cancer, your doctor will advise you on what the best course of treatment is for you. Sometimes chemo is taken orally, sometimes it is injected into the bloodstream, and sometimes chemo is injected directly into the spinal column, organ or body cavity, where the drugs can act more locally and kill cancer cells in the area.


Radiation Therapy

Radiation therapy uses high-energy radiation like x-rays to kill cancer cells or stop them from growing or proliferating. The method of delivery depends on the type and severity of the cancer. There are two main types of radiation therapy:

  • External radiation therapy uses a mechanism outside the body to send radiation towards the cancer
  • Internal radiation therapy uses a radioactive substance, delivered via a needle, catheter, or suppository, which are placed into or near the cancerous growth.

Biologic Therapy or Immunotherapy

Biologic or immunotherapy is a type of cancer treatment that sees to use the body’s own immune system to fight the cancer

Immunotherapy is a type of treatment that uses the body’s own immune system to fight cancer. Here’s how it works: the therapy stimulates your immune system to fight the cancer itself, with the hope of harnessing the power of your own body’s defense system to eradicate the cancer. While some forms of this type of therapy are being used, many are still in the clinical trial stage.

There are various types of biologic therapy, among them:

  • Biological Response Modifiers. Delivered via injection or infusion, this type of immunotherapy is intended to trigger the immune system to indirectly affect tumors, in the hopes of stimulating one’s own immune system to defend itself more successfully against the invading cancer cells.
  • Colony-stimulating factors. Man-made agents, similar to substances in the body that stimulate the production of blood cells, like bone marrow, can help blood-forming tissue recover from the effects of chemotherapy and radiation therapy, and improve immune response to cancer.
  • Tumor vaccines. Still in clinical trials, researchers are working on developing vaccines that can better immune system response to cancer cells by helping the body to better recognize the cancer cells. This is a preventive treatment, which would be given to prevent the cancer from returning, or teach the body to reject the cancerous cells, much like vaccines for diseases like polio, measles, and more.
  • Monoclonal Antibodies. These antibodies, produced in a labe, locate and bind to cancer cells in the body—and can be utilized to detect cancer, or as a therapeutic modality to deliver treatment for the cancer in a very targeted way.

Complementary and Alternative Treatment

If you have colon cancer, research shows that conventional routes of treatment have the highest rates of success. It is critical to work closely with a medical doctor if you have received a diagnosis of colon cancer, as solely relying on complementary treatments has not been proven effective as a stand-alone treatment. Sole reliance on alternative or complementary medicine alone may waste valuable time when the cancer is easiest to treat. However, complementary treatments can be extremely useful and important in the holistic care of your cancer, and can help reduce pain, stress, side effects of medical treatment, and boost overall health. Be sure to speak with your health care professional to see what complementary treatments might be right for you.


Some complementary treatments include:

  • Acupuncture to relieve pain, help alleviate fatigue, decrease nausea, reduce vomiting,
  • Massage therapy can help alleviate muscle tension, stress, anxiety, nausea, and depression in patients with colon cancer undergoing chemotherapy, and has been shown to increase immune system-boosting white blood cells and in dopamine, which is related to a sense of well being.
  • Guided imaging and visualization techniques can help you create a positive mental imagery in which you visualize your cancer being defeated—there is evidence to support that this practice can not only help with possibly reducing cancer progression, it can assist with chemotherapy side effects too
  • Aromatherapy, hypnosis, or energy therapies to help you relax.
  • Herbal or homeopathic medicines for various purposes, such as Danggui (Angelica sinensis-radix) and Ren Shen (Panax ginseng-radix), can be helpful for treatment-related side effects from chemotherapy.

Always talk to your doctor about any medications you take, including herbal and complementary treatments, as they may interact with your other treatments.

Care Guide

In addition to medical and surgical treatment it’s important to take care of yourself. This may include:

  • Learning about your condition and your treatment
  • Talking openly with your family and friends
  • Joining a support group to talk with other colon cancer survivors
  • Asking your doctor about medications that help with side effects such as nausea and fatigue

You can also take better care of yourself with:

  • Healthy eating habits
  • Gentle exercise, such as walking, swimming, or yoga
  • Stress management

When To Contact A Doctor

If you notice any symptoms of colon cancer, like as blood in your stool or a persistent change in bowel habits, make an appointment with your doctor.

Talk to your doctor about when you should begin screening for colon cancer. Guidelines generally recommend colon cancer screenings begin at age 50, but your doctor may recommend more frequent or earlier screening if you have other risk factors, such as a family history of the disease.

 

Questions For Your Doctor

Your medical team may consist of several healthcare professionals, such as a gastroenterologist, medical oncologist, a surgical oncologist, and/or a radiation oncologist. You should seek out a physician who is skilled and knowledgeable, with whom you feel comfortable asking questions and getting the answers you need.

The National Cancer Institute can help you find a cancer center near you.

Questions For A Doctor

When you go to see your doctor, it’s good to have a list of the questions you’d like to have answered. Take a moment to write down some of the things you want to know. Your questions for your doctor might include some of these:

  • Where is my colon cancer located in my colon?
  • What is the stage of my colon cancer?
  • Can you explain my pathology report to me?
  • Can I have a copy of my pathology report?
  • Has my colon cancer spread to other parts of my body?
  • Will I need more tests?
  • What are the treatment options for my colon cancer?
  • Will any of the treatments cure my colon cancer?
  • What is the chance that my colon cancer will be cured?
  • How much does each treatment increase my chances that my colon cancer will be cured?
  • What are the potential side effects of each treatment?
  • How will each treatment affect my daily life?
  • Is there one treatment you feel is best for me?
  • What would you recommend to a family member or friend in my same situation?
  • How much time can I take to make my decision about treatment?
  • Should I seek a second opinion?
  • Should I see a specialist? What will that cost, and will my insurance cover it?
  • Are there any brochures or other printed material that I can take with me? What websites do you recommend?
  • Do my siblings or my children have an increased risk of colon cancer?

In addition to the questions that you’ve prepared to ask your doctor, don’t hesitate to ask questions during your appointment.

Resources

Other useful resources to help you learn about colon cancer can be found at:

American Cancer Society

The National Cancer Institute

ColonCancer.org

The National Colon Cancer Foundation