Cancer Treatment & Information

If you are having rectal bleeding or changes in your bowel movements, you will undergo tests to determine the cause of the symptoms.

• Your health care provider may insert a gloved finger into your rectum through your anus.
• This test, called a digital rectal exam, is a quick screen to make sure that any bleeding is actually coming from your rectum.
• This is not painful, but it is mildly uncomfortable for some people. It takes only a few seconds.

You may have a test called a colonoscopy.

• This is a test that allows a specialist in digestive diseases (a gastroenterologist) to look at the inside of your colon.
• This test looks for polyps, tumors, or other abnormalities.
• Colonoscopy is an endoscopic test. This means that a thin, flexible plastic tube with a tiny camera on the end will be inserted into your colon via your anus. As the tube is advanced further into your colon, the camera sends images of the inside of your colon to a video monitor.
• Colonoscopy is an uncomfortable test for most people. You will first be given a laxative solution to drink that will clear most of the fecal matter from your bowel. You will be allowed nothing to eat before the test. Whenever possible, you will be given medication before the procedure to relax you and relieve the discomfort.
• Flexible sigmoidoscopy is similar to colonoscopy but does not go as far into the colon. It uses a shorter endoscope to examine the rectum, sigmoid (lower) colon, and most of the left colon.

Air-contrast barium enema is a type of x-ray that can show tumors.

• Before the x-ray is taken, a liquid is introduced into your colon and rectum via your anus. The liquid contains barium, which shows up solid on x-rays.
• This test highlights tumors and certain other abnormalities in the colon and rectum.
• Other types of contrast enemas are available.
• Air-contrast barium enema frequently detects malignant tumors, but it is not as effective in detecting small tumors or those far up in your colon.

If a tumor is identified in the colon or rectum, you will probably undergo CT scan of your abdomen and a chest x-ray to make sure the disease has not spread.

What are the symptoms of Colorectal Cancer?

Cancer of the colon and rectum can exhibit itself in several ways. If you have any of these symptoms, seek immediate medical help.
You may notice bleeding from your rectum or blood mixed with your stool.

• People commonly attribute all rectal bleeding to hemorrhoids, thus preventing early diagnosis owing to lack of concern over “bleeding hemorrhoids.”
• Rectal bleeding may be hidden and chronic and may show up as an iron deficiency anemia.
• It may be associated with fatigue and pale skin.
• It usually, but not always, can be detected through a fecal occult (hidden) blood test, in which samples of stool are submitted to a lab for detection of blood.

If the tumor gets large enough, it may completely or partially block your colon. You may notice the following symptoms of bowel obstruction:

• Abdominal distension: Your belly sticks out more than it did before without weight gain.
• Abdominal pain: This is rare in colon cancer. One cause is tearing (perforation) of the bowel. Leaking of bowel contents into the pelvis can cause inflammation (peritonitis) and infection.
• Unexplained, persistent nausea or vomiting
• Unexplained weight loss
• Change in frequency or character of stool (bowel movements)
• Small-caliber (narrow) or ribbon-like stools
• Sensation of incomplete evacuation after a bowel movement
• Rectal pain: Pain rarely occurs with colon cancer and usually indicates a bulky tumor in the rectum that may invade surrounding tissue.

Studies suggest that the average duration of symptoms (from onset to diagnosis) is 14 weeks. There is no association between overall duration of symptoms and the stage of your tumor.

How is Colorectal Cancer diagnosed?

Colon and rectal cancers are diagnosed using the screening tests mentioned below. These tests are used to detect precancerous polyps or cancer at a colon cancer stage early enough for removal and cure. Digital Rectal Examination or DRE is used to detect tumors in the lower intestine, the rectum and the prostate. A lubricated-gloved finger is inserted into the patient’s rectum by a doctor. The doctor feels for lumps or other abnormalities. Less than 10% of colon cancers can be evaluated this way.

Because blood in the stool or feces is not always visible to the naked eye, the fecal occult blood test (FOBT) is used to detect this hidden (occult) blood. The patient supplies up to six stool specimens in a specially prepared package. The stool is smeared on chemically treated paper, which will turn blue if blood is present.

When FOBT or DRE show signs of cancer, several techniques are available to help the physician visualize the colon. These include colonoscopy, sigmoidoscopy, and double-contrast barium enema. Sigmoidoscopies are limited. This imaging technique only views the rectum and the left side of the colon. Colonoscopy and barium enemas allow the physician to view the entire large intestine.

Both flexible sigmoidoscopy and colonoscopy are invasive procedures that involve moving a fiber optic tube through the rectum and colon to view the intestinal walls. The tube contains a tiny camera that transmits the image to a video screen. The use of an ultrasound (sound wave) scanner can enhance viewing quality. During either sigmoidoscopy or colonoscopy, the physician is able to remove polyps or other abnormalities revealed by the procedures.

Colonoscopy is the most accurate testing method and can reduce cancer incidence by up to 90%. It is indicated for anyone with an increased risk for colorectal cancer, including those with a personal or family history of the disease. For about a day before the procedure the patient eats nothing and drinks a laxative solution that cleans out the colon. Air may be introduced into the intestine to widen it and allow the tube to navigate curves.

Other diagnostic tests include genetic screening, stool DNA testing and virtual colonoscopy.

Virtual Colonoscopy is an experimental technique that provides a three-dimensional image of the colon without using the invasive instruments used in the standard colonoscopy. The procedure itself involves pumping air into the colon and scanning the intestine using computed tomography (CT). It is very safe and takes only about 10 minutes. Follow up colonoscopy is needed if suspicious tissue is found.

There is also another exciting development in imaging of the digestive tract. Cancer research has yielded a small, pill-sized, video camera that can be swallowed. As it winds its way through the digestive tract, the camera beams data to a receiver worn by the patient. The camera is not a replacement for colonoscopy. More testing is needed to determine its value.

What Is Colorectal Cancer?

Inside your abdominal cavity is the long, tubular digestive tract. The second part of this tube — the large intestine — is composed of the colon, which stretches four to six feet, and the rectum, which is only four to six inches long. The inner lining of this “colorectal tube” can be a fertile breeding ground for small tumors, called polyps. About a quarter of all adults in the U.S. over the age of 50 will have at least one colorectal polyp. Most colorectal cancers develop from polyps in glandular tissue of the intestinal lining.

Most polyps are benign, but at least one type is known to be precancerous. Most colorectal cancers develop from polyps in glandular tissue of the intestinal lining.

If colorectal cancer is diagnosed and treated early while the tumor is still localized, the disease is highly curable, with five-year survival rates of about 90%. If the tumor continues to grow, cancer can spread directly through the bowel wall to surrounding tissues and organs, as well as into the bloodstream or lymphatic system. Once the cancer spreads to lymph nodes or other organs, successful treatment becomes more difficult. Depending on how advanced the disease is, five-year survival rates range from 65% to 9%.

Cancers of the colon and rectum are the third most common cancer in the U.S., with approximately 150,000 cases diagnosed each year. Like many cancers, colorectal cancer is of particular concern for people older than age 50. Although detection is often possible at an early stage, many people delay seeking medical care because they are embarrassed or fearful of symptoms related to their bowels. Risk increases significantly after age 50 and continues to increase with age.

What Causes Colorectal Cancer?

Doctors are certain that colorectal cancer is not contagious (a person cannot catch the disease from a cancer patient). Some people are more likely to develop colorectal cancer than others. Factors that increase a person’s risk of colorectal cancer include high fat intake, a family history of colorectal cancer and polyps, the presence of polyps in the large intestine, and chronic ulcerative colitis.

     Diet and colon cancer

Diets high in fat are believed to predispose humans to colorectal cancer. In countries with high colorectal cancer rates, the fat intake by the population is much higher than in countries with low cancer rates. It is believed that the breakdown products of fat metabolism lead to the formation of cancer-causing chemicals (carcinogens). Diets high in vegetables and high-fiber foods such as whole-grain breads and cereals may rid the bowel of these carcinogens and help reduce the risk of cancer.

     Colon polyps and colon cancer

Doctors believe that most colon cancers develop in colon polyps. Therefore, removing benign colon polyps can prevent colorectal cancer. Colon polyps develop when chromosome damage occurs in cells of the inner lining of the colon. Chromosomes contain genetic information inherited from each parent. Normally, healthy chromosomes control the growth of cells in an orderly manner. When chromosomes are damaged, cell growth becomes uncontrolled, resulting in masses of extra tissue (polyps). Colon polyps are initially benign. Over years, benign colon polyps can acquire additional chromosome damage to become cancerous.

      Ulcerative colitis and colon cancer

Chronic ulcerative colitis causes inflammation of the inner lining of the colon. For further information, please read the Ulcerative Colitis article. Colon cancer is a recognized complication of chronic ulcerative colitis. The risk for cancer begins to rise after eight to 10 years of colitis. The risk of developing colon cancer in a patient with ulcerative colitis also is related to the location and the extent of his or her disease.

Current estimates of the cumulative incidence of colon cancer associated with ulcerative colitis are 2.5% at 10 years, 7.6% at 30 years, and 10.8% at 50 years. Patients at higher risk of cancer are those with a family history of colon cancer, a long duration of colitis, extensive colon involvement, and those with primary sclerosing cholangitis (PSC).

Since the cancers associated with ulcerative colitis have a more favorable outcome when caught at an earlier stage, yearly examinations of the colon often are recommended after eight years of known extensive disease. During these examinations, samples of tissue (biopsies) can be taken to search for precancerous changes in the lining cells of the colon. When precancerous changes are found, removal of the colon may be necessary to prevent colon cancer.

      Genetics and colon cancer

A person’s genetic background is an important factor in colon cancer risk. Among first-degree relatives of colon cancer patients, the lifetime risk of developing colon cancer is 18% (a threefold increase over the general population in the United States).

Even though family history of colon cancer is an important risk factor, majority (80%) of colon cancers occur sporadically in patients with no family history of colon cancer. Approximately 20% of cancers are associated with a family history of colon cancer. And 5 % of colon cancers are due to hereditary colon cancer syndromes. Hereditary colon caner syndromes are disorders where affected family members have inherited cancer-causing genetic defects from one or both of the parents.

Chromosomes contain genetic information, and chromosome damages cause genetic defects that lead to the formation of colon polyps and later colon cancer. In sporadic polyps and cancers (polyps and cancers that develop in the absence of family history), the chromosome damages are acquired (develop in a cell during adult life). The damaged chromosomes can only be found in the polyps and the cancers that develop from that cell. But in hereditary colon cancer syndromes, the chromosome defects are inherited at birth and are present in every cell in the body. Patients who have inherited the hereditary colon cancer syndrome genes are at risk of developing large number of colon polyps, usually at young ages, and are at very high risk of developing colon cancer early in life, and also are at risk of developing cancers in other organs.

FAP (familial adenomatous polyposis) is a hereditary colon cancer syndrome where the affected family members will develop countless numbers (hundreds, sometimes thousands) of colon polyps starting during the teens. Unless the condition is detected and treated (treatment involves removal of the colon) early, a person affected by familial polyposis syndrome is almost sure to develop colon cancer from these polyps. Cancers usually develop in the 40s. These patients are also at risk of developing other cancers such as cancers in the thyroid gland, stomach, and the ampulla (the part where the bile ducts drain into the duodenum just beyond the stomach).

AFAP (attenuated familial adenomatous polyposis) is a milder version of FAP. Affected members develop less than 100 colon polyps. Nevertheless, they are still at very high risk of developing colon cancers at young ages. They are also at risk of having gastric polyps and duodenal polyps.

HNPCC (hereditary nonpolyposis colon cancer) is a hereditary colon cancer syndrome where affected family members can develop colon polyps and cancers, usually in the right colon, in their 30s to 40s. Certain HNPCC patients are also at risk of developing uterine cancer, stomach cancer, ovarian cancer, and cancers of the ureters (the tubes that connect the kidneys to the bladder), and the biliary tract (the ducts that drain bile from the liver to the intestines).

MYH polyposis syndrome is a recently discovered hereditary colon cancer syndrome. Affected members typically develop 10-100 polyps occurring at around 40 years of age, and are at high risk of developing colon cancer.