What is Colon Cancer?

Colon cancer is cancer of the colon (large intestine). This is the lower part of your digestive system. When cancer form in the rectum, the last several inches of the colon, it is referred to as rectal cancer. These two cancers together are often referred to as colorectal cancer.

Adenomatous polyps are benign (noncancerous) growths of cells. Over time, some of these polyps can develop into colon cancers. Because polyps are usually small and don’t produce symptoms, doctors recommend regular screening tests to remove polyps. Removal of polyps reduces your chances of developing colorectal cancer.

The current guidelines recommend screening for colon cancer starting at age 50 unless you have other risk factors such as a family history. Your doctor will be able to review your medical history and determine when it is appropriate for you to begin colon cancer screening.

Symptoms of Colon Cancer

Many people do not experience any signs or symptoms of colon cancer, especially during the early stages. Symptoms vary depending on the size of the cancer and the location within the colon.

  • Change in bowel habits lasting longer than 4 weeks – can be diarrhea, constipation, or change in consistency
  • Persistent abdominal discomfort – gas, pain, cramps
  • Rectal bleeding or blood in your stool
  • Weakness or fatigue
  • Feeling as if your bowel isn’t completely emptying
  • Unexplained weight loss

Anytime you notice these changes or symptoms, it is important to see your doctor for evaluation.

What Causes Colon Cancer?

Most of the time, it is not certain what has caused a colon cancer. Colon cancer develops when healthy cells in the colon develop errors within their DNA. A healthy cell will divide in an orderly way but if the DNA is damaged from cancer, the cells continue to divide at will. Over time the cells will accumulate and form a tumor. They will continue to grow and invade and destroy normal tissue nearby. Cancerous cells are also able to travel to other parts of the body.

There are two causes that have been found to increase a person’s risk of colon cancer:

  • Inherited Gene Mutations – This group is responsible for only a small percentage of colon cancer. The gene mutations are passed through families but having this mutation doesn’t mean developing cancer is inevitable, just the risk is significantly greater. Both of these conditions can be detected through genetic testing.
    • Hereditary nonpolyposis colorectal cancer (HNPCC) – also known as Lynch Syndrome, increases risk of colon and other cancers, tendency to develop colon cancer prior to age 50.
    • Familial adenomatous polyposis (FAP) – rare disorder in which thousands of polyps in the lining of the colon and rectum are developed, those with untreated FAP have a greater risk of developing colon cancer prior to age 40.
  • Dietary Factors
    • Studies have shown a Western diet, high in fat and low in fiber, does increase the risk of colon cancer. There is no clear understanding of why this occurs and researchers are actively looking at it.

Other factors that can increase your risk of colon cancer are:

  • Older age – majority of people are over the age of 50
  • African American Race
  • Personal history of colorectal cancer or polyps
  • Inflammatory intestinal conditions – ulcerative colitis, Crohn’s disease
  • Inherited symdromes – HNPCC, FAP
  • Family history of colon cancer
  • Low-fiber, high fat diet
  • Sedentary lifestyle
  • Diabetes
  • Obesity
  • Smoking
  • Alcohol
  • Radiation therapy for cancer

Screening Recommendations

The current recommendations for healthy people with no sign or symptoms and no family history is to begin screening at age 50. People with an increased risk, such as family history, African Americans, and Native Americans may need to consider beginning screening sooner due to a higher risk.

When colon cancer is found in its early stages, there is a greater chance for cure and your risk of dying from colon cancer is reduced. There are several screening options available and it is important for you to discuss your options with your doctor to determine which one is the most appropriate for you.

Diagnosis of Colon Cancer

If you have signs or symptoms of colon cancer, your doctor may recommend one or more tests or procedures. These can include:

  • Colonoscopy  – allows the doctor to view the lining of your colon and rectum and take tissue samples for analysis
  • Blood Tests – No blood test can be used to determine if you have cancer. Blood tests are used to determine your overall health. CEA (carcinoembryonic antigen) is a chemical sometimes produced by colon cancers and able to be detected in the blood. The level of CEA in your blood can assist your doctor in determining your response to treatment and overall prognosis.

Colon Cancer Staging

Staging is used to determine the extent of your cancer and what treatments will be the most appropriate for you. Staging may be done through abdominal and chest CT scans, endoscopic ultrasound, however, sometimes it may not be able to be determined until after colon cancer surgery.

The states of colon cancer are:

  • Stage 1 – your cancer has grown through the superficial lining of the colon or rectum but hasn’t spread beyond the wall of the colon or rectum.
  • Stage 2 – your cancer has grown into or through the wall of the colon or rectum but hasn’t spread to your lymph nodes.
  • Stage 3 – your cancer has invaded nearby lymph nodes but isn’t affecting other parts of your body.
  • Stage 4 – your cancer has spread to distant sites, such as other organs.

Treatments

There are several different ways to treat colon cancer and their use depends on the stage of your cancer. Your doctor and/or surgeon will discuss all of your options with you prior to any treatment decisions.

  • Early stage colon cancer
    • Polyp removal during colonoscopy – if your cancer is very small, localized into a polyp and is at an early stage, your doctor may be able to completely remove it during your colonoscopy.
    • Endoscopic mucosal resection – this procedure is done for removing larger polyps and involves taking a small amount of the colon lining with the polyp.
    • Minimally invasive surgery – for those polyps unable to be removed during colonoscopy, your surgeon may perform laparoscopic surgery. Several small incisions are made in your abdominal wall and instruments with cameras are inserted. The area of your affected colon is then viewed and the polyp is removed through the small incisions. Lymph node samples from the area may also be taken at that time.
  • Invasive colon cancer
    • Partial colectomy – your surgeon removes the portion of your colon containing the cancer along with a portion of normal tissue on either side of it. The healthy portions of your colon are then reconnected.
    • Colostomy – if your surgeon is unable to reconnect the health portions of your colon, you may need to have a permanent or temporary colostomy. An opening in the wall of your abdomen is created from a portion of the remaining bowel. Waste is eliminated through this opening into a special bag. Not all colostomies are permanent. Some may be created to allow for healing of your colon and plans will be made for reconnection at a later date.
    • Lymph node removal – during colon cancer surgery, nearby lymph nodes are removed and tested for signs of cancer.
  • Advanced colon cancer
    • Surgery during advanced cancer isn’t always done to cure cancer. If your cancer is very advanced or if you have poor overall health, surgery may be done at times to relieve conditions caused by the cancer such as blockage, pain, bleeding. In instances where your overall health is good and the cancer has spread to only one organ such as the liver, surgery may be recommended to remove the cancerous lesion from that organ. In these instances, chemotherapy may be used before or after the surgery.
    • Chemotherapy – uses drugs to destroy the cancer calls and is usually used after surgery when the cancer has spread to the lymph nodes. Chemotherapy can also be used prior to surgery to shrink a cancerous tumor or given to relieve symptoms of colon cancer spread to other parts of the body. Chemotherapy is typically used with radiation therapy before and after surgery for rectal cancer.
    • Radiation Therapy – powerful energy sources are used to destroy any remaining cancer cells after surgery, shrink large tumors prior to surgery, or relieve symptoms from colorectal cancer. As stated earlier, radiation is used as a routine part of treating rectal cancer.
    • Targeted Drug Therapy – a special form of drug therapy in which the specific defects in the cell allowing growth of the cancer cell is targeted. These drugs can be used with or without chemotherapy and not all people benefit from their use. Doctors must weigh the risk of side effects and the expensive cost against the limited benefit prior to initiating treatment.
    • Palliative Care – supportive care provided to complement your other treatments. It focuses on providing relief from pain and other symptoms and is aimed to improve the quality of life for people with cancer and their families.
    • Alternative Medicine – There is no alternative medicine found to cure colon cancer. Alternative treatments are used to relieve distress and help you cope with the cancer diagnosis. Common alternative treatments include: art therapy, dance, exercise, meditation, music therapy, and relaxation.

Coping and Support after Diagnosis

All people are different and everyone reacts to a colon cancer diagnosis differently. For all, it is a time of uncertainty and distress and each person learns to cope in their own way. The following are ways to help you in this process:

  • Know what to expect – learn as much as you can about your type of cancer, stage, treatment options, and possible side effects so you and your family can made informed decisions.
  • Keep friends and family close – these people can provide the practical and emotional support you will need as you go through this time.
  • Find someone to talk to – find a good listener, this can be a friend, family member, counselor, social worker, or clergy member. Support groups can also be helpful during this time and your doctor may be able to assist you in locating one appropriate for you.

Prevention

It is important to get your screening for colon cancer at age 50 or sooner if you are at an increased risk. There are many options for colon cancer screening and your doctor will discuss the benefits and drawbacks of each option. Your doctor work with you to determine what tests are appropriate for you.

Lifestyle changes can also reduce your risk for colon cancer:

  • Eat a variety of fruits, vegetables, and whole grains – the vitamins, minerals, and antioxidants found in these foods may play a role in cancer prevention.
  • Drink alcohol in moderation, if at all – it is recommended women have no more than one drink per day and men no more than two.
  • Stop smoking
  • Exercise – 30 minutes of exercise most days is recommended. You may need to work your way up to this point if you haven’t been exercising. As always, speak with your doctor prior to starting any form of exercise program.
  • Maintain a healthy weight – work to maintain your weight by combining healthy eating and exercise. If you need to lose weight, speak with your doctor about healthy ways you can achieve weight loss.