Love Thyself Series: Colon Cancer Screening

In North America and Western Europe, the second leading cause of death due to cancer is colorectal cancer (CRC). The disease progresses slowly taking up to 10 years for the normal lining of the colon to change to cancer. Since the disease progression can take up to 10 years, this affords the chance to use procedures for screening in an effort to detect polyps. Polyps are growths that begin in the colon and rectum and are considered to be the most common precursors to colon cancer. The size and appearance of the polyps may vary. When polyps are small, they have the appearance of a wart and as they grow the appearance changes to that of a mushroom with a stalk. The polyps found in the rectum and colon are usually benign (non malignant) and exhibit no symptoms. Without screening, detecting colorectal cancer can be is almost impossible because most people are usually asymptomatic. In this article I will focus on the signs and symptoms of colorectal cancer in addition to the procedures used for screening to detect polyps that are the precursors to colon cancer.
Symptoms
Most people with CRC are asymptomatic or experience non-specific symptoms until the cancer becomes advanced. The most common symptoms of cancer or precancerous polyps are blood in the stool, a change in bowel habits, and pain to the abdomen which is much less common. Symptoms also can include fatigue, weakness and iron deficiency anemia. If detected and removed in the premalignant or early stages, the development or spread of the cancer is prevented. Without screening, detecting CRC in its early stages can be difficult. Current evidence shows that screening individuals who are asymptomatic or of average risk reduces the mortality rate for CRC, because cancers can be prevented if polyps can be removed. Early detection is imperative in the prevention of CRC.
Sigmoidoscopy and Colonoscopy
According to the American Cancer Society, a screening flexible sigmoidoscopy should be done at age 50 for individuals without a family history of colon cancer. This procedure has been proven to decrease the mortality and incidence rate of colon cancer. If patients have a first-degree relative of age 60 years or less that have had CRC, a more intensive screening may be needed such as a colonoscopy or a barium enema x-ray. The flexible sigmoidoscopy examines the lower 1/3 of the colon where 2/3 of polyps or cancers occur. This test takes approximately 3 to 5 minutes and requires no sedation. This procedure can cause a little discomfort, but it reduces the chances of developing CRC. According to an article written by a board certified gastroenterologist, a flexible sigmoidoscopy can detect approximately 65%-75% of polyps and 40%-50% of CRC.
A colonoscopy is considered to be the most conclusive test for colon cancer screening. The procedure is performed by a board certified gastroenterologist; utilizes a longer version of the sigmoidoscopy instrument. It is a flexible fiberoptic tube that is used to visualize the entire colon. Prior to the procedure the patient is given valium and a narcotic. There are some risks associated with the procedure and they are discussed with the physician prior to the exam. The current indications for a colonoscopy include: a positive test of blood found in stool, a poly (adenomatous) found on flexible sigmoidoscopy exam greater than 5mm, family history of 2 relatives with colon cancer or one first degree relative with colon cancer 60 years or less, unexplained diarrhea, and occasionally for some types of abdominal pain.
According to Rao and Goodin, the third most common cause of cancer deaths in women is CRC. The rate of colon cancer remains high for African Americans compared to other ethnic groups. The probable cause of this disparity is attributed to lack of quality healthcare in the lower socioeconomic communities. Since CRC is so slow growing, screening and early detection is imperative. If detected early through one of the screening exams, CRC can be prevented. One should check with his or her primary physician to determine which screening method is appropriate.