The basics of colorectal cancer

Colorectal cancer is the fourth most common cause of cancer-related death in the United States, according to data from the Centers for Disease Control and Prevention. Despite that, colorectal cancer does not garner as much attention as many think it should.

The Mayo Clinic says colorectal cancer starts in the large intestine (colon), which is the final part of the digestive tract, or in the rectum. It usually begins as noncancerous clumps of cells known as polyps. Over time, some of those benign polyps can change into cancerous cells and eventually tumors. The entire colon is about five feet in length, which provides a lot of real estate where cancer can start.

As with any type of cancer, detecting colorectal cancer early can make a difference in treatment. Early discovery of polyps that may turn cancerous can give doctors and their patients more treatment options. Medical professionals use colonoscopy, which is a camera inserted into the colon, to check for abnormalities. The American Cancer Society now recommends that a person without any risk factors have their first colonoscopy at age 45. This procedure often is done under a mild sedation and the patient feels no discomfort. Healthy people can go 10 years between colonoscopies.

The camera will provide images of the tissue inside the colon and detect if polyps are present. The ACS says there are three different types of polyps.

• Adenomatous polyps: ese sometimes change into cancer and are considered a pre-cancerous condition.

• Hyperplastic and inammatory polyps: ese are more common, but in general they are not pre-cancerous.

• Sessile serrated polyps and tradi – tional serrated adenomas: ese polyps have a higher risk of colorectal cancer formation.

Sometimes doctors will remove polyps if they think they may grow into cancer.

Most colorectal cancers are known as adenocarcinomas, and start in the cells that make mucus to lubricate the inside of the rectum and colon. When doctors are referring to colorectal cancer, they often are discussing adenocarcinoma.

If colorectal cancer is not caught early when the cancer cells are in the colon walls, it can then grow into blood vessels or lump vessels and travel to distant parts of the body.

Certain symptoms and signs may provide clues that colorectal cancer is present, apart from results from imaging tests, offers the Mayo Clinic.

• Persistent changes in bowel hab its, including changes in the consistency of stool and frequency of movements.

• Bleeding from the rectum or blood found in stool.

• Abdominal discomfort, which can include cramps or gas pains.

• A persistent feeling that the bow el hasn't emptied completely.

• Unexplained weight loss. Treatment for colorectal cancer depends on staging. Plans can be discussed with an oncologist if cancer is detected.

More information about colorectal cancer is available at www.cancer.org.