What is Colorectal Cancer?

The colon and rectum together form the portion of the digestive tract known as the large intestine or large bowel. Because colon and rectal cancers have many features in common, they are sometimes referred to together as colorectal cancer.

Colorectal cancer is the third most common cancer in the United States, according to the American Cancer Society. Thanks to early detection and the use of routine screening tests such as colonoscopy, the rate of colon cancer is declining, and many cancers are being detected at earlier stages when the cure rate is highest.

If an abnormal growth forms in the intestine, you may become aware of unusual signs related to bowel movements. However, not every problem means a cancerous growth. There are a variety of benign growths or tumors which can effect the digestive system.

A polyp is a relatively common benign tumor which grows from the wall of the colon or rectum. Colorectal polyps should be removed, however, because they can become cancerous. People who have had one polyp are prone to future polyps as well. The number of new cases of colorectal cancer, and the number of deaths due to colorectal cancer, have decreased, which is attributed to increased screening and polyp removal.

Once a colon or rectal cancer does develop, it can invade and destroy nearby tissues and organs, enter the bloodstream and travel to nearby lymph nodes. Once in the lymphatic system, colorectal cancer can spread to other parts of the body such as the bones, bladder, liver, lungs, and brain. The spread of cancer cells to other areas of the body is known as metastasis.

What are the symptoms of Colorectal Cancer?

The warning signs that could indicate a problem in the colon or rectum include:

• A change in bowel habits
• Diarrhea or constipation
• Bright red or very dark stools which could indicate blood
• Stools smaller in width than usual
• Frequent gas pains
• A feeling the bowel does not empty completely
• Bloating, cramps or fullness in the stomach
• Decreased appetite
• Vomiting
• Unexplained weight loss
• Constant fatigue
• Jaundice-yellowing of the skin and eyes

These symptoms can have many causes including the flu, ulcers, and an inflamed colon in addition to cancer. It is also possible to have colon cancer and not have any symptoms. Always consult your physician for a diagnosis.

What are the risk factors for colorectal cancer?

Risk factors may include:

• Age – Most people who have colorectal cancer are over age 50, however, it can occur at any age.
• Diet – Colorectal cancer is often associated with a diet high in fat and calories, and low in fiber.
• Polyps – Benign growths on the wall of the colon or rectum are common in people over age 50, and are believed to lead to colorectal cancer. Skin tags anywhere on the body, may be associated with polyps.
• Personal History – People who have had colorectal cancer, as well as ovarian, uterine, or breast cancers, have a slightly increased risk for colorectal cancer.
• Family History – People with first-degree relatives who have had colorectal cancer have an increased risk for colorectal cancer.
• Ulcerative Colitis – People who have ulcerative colitis, an inflamed lining of the colon, have an increased risk for colorectal cancer.

What causes colorectal cancer?

The exact cause of most colorectal cancer is unknown, but the known risk factors listed above are the most likely causes. Less than 10 percent of colorectal cancers are caused by inherited gene mutations. People with a family history of colorectal cancer may wish to consider genetic testing. The American Cancer Society suggests that anyone undergoing such tests have access to a physician or geneticist qualified to explain the significance of these test results.

Colorectal Cancer Screening Guidelines

According to the most recent recommendation from the American Cancer Society, beginning at 50 years of age, men and women should begin screening with one of the examination schedules below:

• A fecal occult blood test (FOBT) or fecal immunochemical test (FIT) every year
• A flexible sigmoidoscopy (FSIG) every 5 years
• Annual FOBT or FIT and flexible sigmoidoscopy every 5 years*
• A double-contrast barium enema every 5 years
• A colonoscopy every 10 years

*Combined testing is preferred over either annual FOBT or FIT, or FSIG every 5 years alone. All positive tests should be followed up with a colonoscopy.

Individuals should be screened earlier and/or more frequently if they have:

• Personal history of colorectal cancer or adenomatous polyp
• Strong family history of colorectal cancer or polyps (cancer or polyps in a first degree relative younger than 60 or in two first degree relatives at any age)
• Personal history of chronic inflammatory bowel disease
• Family history of a hereditary colorectal cancer syndrome (familial adenomatous polyposis or hereditary polyposis colorectal cancer)

Diagnosis

To determine if your symptoms indicate a colorectal cancer, your physician must first take your personal and family history. That is followed by a thorough physical examiniation and laboratory tests. Some of the tests in the colorectal examination may include:

• Digital rectal examination (DRE) – a physician or healthcare provider inserts a gloved finger into the rectum to feel for anything unusual or abnormal.
• Fecal occult blood test – checks for hidden blood in the stool. It involves placing a very small amount of stool on a special card, which is then tested in the physician’s office or sent to a laboratory.
• Sigmoidoscopy – a diagnostic procedure that allows the physician to examine the inside of a portion of the large intestine (the left side, up to 90 cm or approximately 12 inches.) A short, flexible, lighted tube, called a sigmoidoscope, is inserted into the intestine through the rectum. The scope blows air into the intestine to inflate it and make viewing the inside easier. About 50 percent of colon and rectal cancers can be found with this procedure.
• Lower GI series – also called a barium enema, this is an x-ray examination of the colon and rectum. A fluid called barium (a metallic, chalky liquid used to coat the inside of organs so that they will show up on an x-ray) enables the physician to see narrowed areas, or obstructions which may indicate a problem.
• Colonoscopy – This is an examination of the inside of the entire colon done with a long, flexible, lighted instrument called a colonoscope. If a polyp or abnormal growth is found the physician can remove part or all of it through the colonoscope. The tissue is then checked under a microscope for cancer cells in a procedure known as a biopsy. If the biopsy shows the presence of cancer cells, the patient next undergoes staging examinations to determine if the disease has spread. The staging tests may include further x-rays, ultrasonography or CT scans. Blood tests known as CEA assay tests may also be done to measure a protein called carcinoembryonic antigen, which is sometimes higher in patients who have colorectal cancer.

Treatment for colorectal cancer

Each patient’s course of treatment is individualized. As no two cancers are exactly alike, so no two courses of treatment are necessarily alike. Treatment choices for the person with colon cancer depend on the stage of the tumor, if it has spread, and how far. When the disease has been found and staged, the physician will suggest a treatment plan. Treatment may include:

• Colon sugery – the most common treatment for colorectal cancer. The extent and type of surgery will depend upon the size, type and location of the tumor. In a partial colectomy, the cancerous part of the colon or rectum is removed along with some surrounding healthy tissue. Nearby lymph nodes are also removed for later examination to determine the stage of the cancer. If the lymph nodes are cancer free, it is possible no other treatment will be needed. Usually, during the surgery the physician reconnects the healthy sections of the colon. If this is not possible, then a colostomy, or opening in the abdomen, is created so that patients may rid their bodies of solid waste. Such a colostomy may be temporary or permanent depending on the circumstances. Surgery may be used solely for the treatment of colorectal cancer, or in combination with other forms of treatment such as chemotherapy or radiation.

Huntington Hospital’s team of colorectal surgeons provides patients with the most advanced surgical care available. Laparoscopic surgery is now a viable option for many colon cancer patients. In this procedure, surgical instruments are inserted through tiny incisions with the surgical field projected onto a video monitor. These smaller incisions have resulted in shorter recovery periods, less pain, and reduced hospital stays. Among the benefits of laparoscopic colon cancer surgery is the patients’ ability to return to their normal activities much quicker.

Chemotherapy – the use of drugs to destroy cancer cells. It too can be used as the only mode of treatment or in combination with other forms of treatment. Chemotherapy can be given following surgery to prevent further spread of disease or for patients with advanced, metastatic colon cancer, to control their disease. Chemotherapy may also be given prior to surgery to shrink the size of the tumor. Chemotherapy is usually administered in cycles. Drugs are given orally or by injection for a period of time after which patients are given time for recovery. Chemotherapy is usually given on an outpatient basis, although, occasionally a short hospital stay is necessary. (more info)

Remarkable new treatments for colon cancer are now available at Huntington Hospital. These include both new chemotherapies with less side effects and targeted therapies, some of which, for example, work by attacking the blood supply that provides tumor cells with the nourishment necessary for growth. When combined in the treatment of advanced, Stage IV colon cancer, these drugs have doubled the length of survival. Clinical trials are now being designed to apply these therapies in earlier stage cancers as well.

Radiation therapy – the use of high-energy radiation to kill cancer cells and halt their spread, is recommended for the treatment of rectal cancer only. Radiation therapy can be used in combination with surgery, usually after or sometimes before, the surgical procedure. Chemotherapy in combination with radiotherapy is sometimes used prior to surgery to decrease the size of the tumor/s and has been shown to reduce the risk of recurrence. Radiation is usually given on an outpatient basis five days a week for several weeks. (more info)

Endorectal brachytherapy, a new treatment for some rectal cancer patients, is now available at Huntington Hospital. Usually an outpatient procedure, the treatment radiation is delivered via a plastic applicator which is placed in the rectum. The applicator is scored with channels. Only those channels that will be in direct contact with the tumor are loaded with radiation to deliver the maximum dose to the cancer while sparing the rectum walls and other internal organs. Studies have shown that this treatment doubles the patient’s chance of undergoing anal preservation surgery and reduces the odds of the patient requiring a permanent colostomy. The treatment also minimizes the side effects of traditional external beam radiation. Endorectal brachytherapy is not recommended for all rectal cancer patients.

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