What is Hereditary Nonpolyposis Colorectal Cancer?

Hereditary nonpolyposis colorectal cancer affects various parts of the digestive track and other areas of the body. The most common locations are the colon and rectum, but the liver, gallbladder and the female reproductive organs can be affected as well. The disorder, which is also known as Lynch syndrome, is generally inherited from one or both parents, and it involves malfunctioning genes. The genes that cause hereditary nonpolyposis colorectal cancer are actually present in every cell in a person’s body, and that’s the reason it can affect such a wide range of areas.

The nonpolyposis part of the name refers to the fact that, originally, doctors didn’t think this disorder involved colon polyps—later research has disproved this. Colon polyps aren’t uncommon with the disorder, and they happen at a younger age, with a higher risk of becoming cancerous. When trying to diagnose hereditary nonpolyposis colorectal cancer, colon polyps are one of the first things a doctor will generally look for.

Approximately 160,000 cases of colorectal cancers are diagnosed in the US every year, and among those, about 3% are related to hereditary nonpolyposis colorectal cancer. If a person has a family history of colorectal cancer, a deoxyribonucleic acid (DNA) test can be a good way to rule out a possibility of the disease. Doctors generally recommend being concerned if a person has three relatives with the disorder, especially if the history of the disease goes back to three generations. Many people who are diagnosed with hereditary nonpolyposis colorectal cancer develop problems prior to the age of 50, and that’s one thing that separates this disorder from other colorectal cancers.

Doctors who suspect hereditary nonpolyposis colorectal cancer will generally order a colonoscopy. This is a procedure in which a doctor uses a thin plastic tube with a camera attached to examine the insider of a person’s colon. The day before surgery, a person will generally be given a drug that causes evacuation of the bowels. During the colonoscopy, the patient is normally sedated. While preforming the procedure, doctors may remove any polyps they see and take tissue samples for testing. Patients are usually allowed to go home on the same day as the colonoscopy, but because of the drugs used in sedation, they will generally need a designated driver.

If any signs of cancer are found during the colonoscopy, the most common approach is to remove the colon. This is generally done right away, because the risk of spreading is so great. When removing the colon, there are several surgical procedures available to physicians. Some methods leave the bowel functional, while others require the patient to wear a bag attached to her digestive system for waste collection. After surgery, most patients are able to resume relatively normal eating habits, but they may experience more frequent bowel movements.