Q. What is Colon Cancer?

Our bodies are made up of billions of cells that grow, divide, and then die in a predictable manner. Cancer occurs when something goes wrong with this system, causing uncontrolled cell division and growth. The cancer cells lump together and form a mass of extra tissue, also known as a cancerous tumor. When cancer cells are present in the colon, it's referred to as colon cancer.

Anatomy of the Colon

The colon is about 6 feet long and is the part of the body's digestive system that moves waste material from the small intestine to the rectum. The colon is comprised of four distinct layers: the mucosa, the submucosa, the muscularis externis, and the serosa.

Colon Cancer Symptoms

Since colon cancer can grow for years without causing any symptoms, it's best to get regular colon cancer screenings. But, knowing what to look out for can't hurt. Examples of symptoms include thin stools, stomach cramping, unexplained weight loss, and fatigue.

Risk Factors for Colon Cancer

Being age 50 or older is actually the number one risk factor for colon cancer. But other things impact colon cancer development, too. For example, studies indicate that alcohol, smoking, inflammatory bowel disease, and obesity can all increase a person's risk of developing colon cancer.

Colon Cancer Diagnosis

For some, a colon cancer diagnosis comes after months of trying to pinpoint the cause of various symptoms. Others receive a surprise diagnosis after a routine colonoscopy. Although there are many ways to arrive at a colon cancer diagnosis, they all have one thing in common: laboratory analysis of a tissue sample that confirms the presence of cancer.

Types of Colon Cancer

The type of colon cancer is usually defined by what kind of cell or tissue (collection of cells) it originates in. For example, the most common type of colon cancer is adenocarcinoma (literally, "cancer of a gland"). But colon cancer can begin in other types of cells, too. Colon lymphoma, which is rare but does occur, begins in a lymphocyte (lymph cell). Leiomyosarcoma of the colon, which is also rare, is a cancerous tumor that begins in one of the muscle layers of the colon.

Stages of Colon Cancer

There are five colon cancer stages (0-4). Colon cancer used to be rated using the Duke's system. For example, Duke's A cancer was the equivalent of stage 1 cancer. Sometimes you'll still hear people refer to their tumors that way, which can cause some confusion. This staging system reflects where the cancer went when no one was looking. In general, the earlier the stage, the easier the cancer is to treat.

Colon Cancer Treatment

There are three standard colon cancer treatments: surgery, chemotherapy, and radiation therapy. Another potential option for some patients is immunotherapy. But, surgery is the most common treatment and is often combined with chemo/radiation to treat later-stage cancers.

Colon Cancer Survival Rates

When faced with the uncertainty of cancer, it's human nature to learn as much as we can about it and try to figure out how it's all going to play out. Of course we can't really know, but that's not the point. It's important to remember that colon cancer survival rates are generalizations and your individual chances of survival may be quite different.

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