You’ve probably heard about colorectal cancer at some point in your life. Well, this type of cancer starts in the colon or the rectum and can also be called colon cancer or rectal cancer, depending on where they start. Colon cancer and rectal cancer are often grouped together since they have many features in common.
To better understand colorectal cancer, you need to be aware of the normal structure and function of the colon and rectum. In a nutshell, the colon and rectum make up the large intestine, which is part of the digestive system, also called the gastrointestinal system.
Most of the large intestine is made up of the colon, a muscular tube about 5 feet long. That brings the question; how does colorectal cancer start? Well, most colorectal cancers start as a growth on the inner lining of the colon or rectum. These growths are called polyps.
Most polyps are benign, or noncancerous. However, some types of polyps can change into cancer over time. The chance of a polyp turning into cancer depends on the type of polyp is. Keep in mind there are different types of polyps including; adenomatous polyps, hyperplastic polyps, and sessile serrated polyps.
In the event that cancer forms in a polyp, it can grow into the wall of the colon or rectum over time. The wall of the colon and rectum is made up of many layers. Colorectal cancer is known to start in the innermost layer and can grow outward through some or all of the other layers.
When cancer cells are in the wall, they can eventually grow into blood vessels or lymph vessels. From there, they can travel to nearby lymph nodes or to distant parts of the body. The stage of a colorectal cancer depends on how deeply it grows into the wall and if it has spread outside the colon or rectum.
As we conclude, you should remember that most colorectal cancers are adenocarcinomas. These cancers start in cells that make mucus to lubricate the inside of the colon and rectum. When doctors talk about colorectal cancer, they are almost talking about this type.
Some subtypes of adenocarcinoma, such as signet ring and mucinous, may have a worse prognosis than other subtypes of adenocarcinoma. Be sure to look more into the signs and symptoms of colorectal cancer and seek medical attention as early as possible.