- The colon, also known as the large intestine, is the last part of the digestive tract.
- The rectum is the very end of the large intestine that opens at the anus.
Facts About Colon Cancer
About 150,000 new cases of colorectal (colon and rectal) cancer are diagnosed each year in the U.S., making it the second most common type of cancer and the second leading cause of cancer death in the U.S.
One-third of all colorectal cancers are found in the rectum; the rest are found in other parts of the colon.
Screening for colorectal cancer should begin at the age of 40 in healthy adults. Seventy to 80 percent of colorectal cancer cases occur in adults without specific risk factors.
Widespread screening for colorectal cancer could save up to many lives each year.
Early detection reduces the probability of major surgery and increases chances of cure.
Risk increases after age 40.
Both men and women are equally at risk for colorectal cancer.
In the U.S. the death rate for colorectal cancer is declining. This may be due to a higher rate of screening for the disease.
Colon cancer may affect any racial or ethnic group; however, some studies suggest that Americans of northern European heritage have a higher-than-average risk of colon cancer.
CausesThere are several causes for colorectal cancer as well as factors that place certain individuals at increased risk for the disease. There are known genetic and environmental factors.
- The biggest risk factor is age. Colon cancer is rare in those under 40 years. The rate of colorectal cancer detection begins to increase after age 40. Most colorectal cancer is diagnosed in those over 60 years.
- Have a mother, father, sister, or brother who developed colorectal cancer or polyps. When more than one family member has had colorectal cancer, the risk to other members may be three-to-four times higher of developing the disease. This higher risk may be due to an inherited gene.
- Have history of benign growths, such as polyps, that have been surgically removed.
- Have a prior history of colon or rectal cancer.
- Have disease or condition linked with increased risk.
- Have a diet high in fat and low in fiber.
SymptomsThe symptoms of colon cancer can be confused with those of a number of digestive disorders. Having one or more of these symptoms does not mean you have cancer. In all cases, people with the following symptoms should contact their doctor:
- Bleeding from the rectum. Sometimes blood can be seen on the toilet tissue or in the toilet bowl after a bowel movement. Other things can cause rectal bleeding other than cancer, but rectal bleeding should never be ignored.
- Changes in bowel habits. These are not usually caused by cancer; however, be sure to discuss such changes with a doctor. If diarrhea or constipation lasts for more than two weeks or bowel habits go back and forth between diarrhea and constipation, or if the stool is unusually narrow, consultation should be made with a doctor.
- Pain in the abdomen or rectum. Discomfort or dull, vague, or sharp pain in the abdomen or rectum may have a number of possible causes. It does not mean that cancer is present but you should make an appointment with your physician.
- A feeling that a bowel movement cannot be completed.
- Unexplained weight loss, unusually low red blood cell counts or anemia, paleness, fatigue, or a yellowish coloring of the skin or whites of the eyes.
Diagnosisf people experience symptoms like those of colorectal cancer, they need to make an appointment with their family physician, a gastroenterologist, a physician specially trained in the management of digestive system disorders, or a colon and rectal surgeon, a specialist in treatment of diseases of the colon.
The doctor performs a thorough clinical evaluation that includes:
- A complete medical, family, and drug history
- A physical examination, including a digital rectal examination
Double contrast barium enema (also called barium meal and enema)
TreatmentThe outlook for people with colon cancer has improved steadily in recent years. Three types of treatment are available for individuals with colon cancer:
- Surgery is an operation that involves removing the cancerous section of the colon. This is the primary treatment for colon cancer for most individuals.
The goal of surgery for colorectal cancer is to eliminate the cancer or, in the case of advanced disease, relieve symptoms.
- With the exception of some less serious operations performed through the anus, surgery for colorectal cancer is a major operative procedure.
- Some very early, small colorectal cancers may be removed with a colonoscope.
- In most cases, a major operation is required and a length of the intestine is removed. But even when a large part of the intestine is removed, most people function as well as they did before the surgery.
- Chemotherapy involves treatment with drugs that destroy fast-growing cells, like cancer cells. This treatment is given to persons with advanced cancers that have spread outside of the colon.
- Radiation therapy is a specialized treatment using radiation to destroy rapidly growing cancer cells. This is usually reserved for treatment of rectal cancer and may be given before surgery, often in combination with chemotherapy. This treatment may shrink the tumor and improve the chances of avoiding a permanent colostomy in select persons.
Fatigue may be related to decreased metabolic energy production, increased energy requirements (hypermetabolic state), overwhelming psychologic/emotional demands, and altered body chemistry (side effects of medications, chemotherapy), possibly evidenced by unremitting/overwhelming lack of energy, inability to maintain usual routines, decreased performance, impaired ability to concentrate, lethargy/listlessness, and disinterest in surroundings.
Fear/death Anxiety may be related to situational crises, threat to/change in health/socioeconomic status, role functioning, interaction patterns; threat of death, separation from family, interpersonal transmission of feelings, possibly evidenced by expressed concerns, feelings of inadequacy/helplessness, insomnia; increased tension, restlessness, focus on self, sympathetic stimulation.
Anticipatory Grieving may be related to potential loss of physiologic well-being (body part/function), perceived separation from SO(s)/lifestyle (death), possibly evidenced by anger, sadness, withdrawal, choked feelings, changes in eating/sleep patterns, activity level, libido, and communication patterns.
Acute/chronic Pain may be related to the disease process (compression of nerve tissue, infiltration of nerves or their vascular supply, obstruction of a nerve pathway, inflammation) or side effects of therapeutic agents, possibly evidenced by verbal reports, self-focusing/narrowed focus, alteration in muscle tone, facial mask of pain, distraction/guarding behaviors, autonomic responses, and restlessness.
Impaired Home Maintenance may be related to debilitation, lack of resources, and/or inadequate support systems, possibly evidenced by verbalization of problem, request for assistance, and lack of necessary equipment or aids.