Colorectal cancer has many known risk factors. Some are lifestyle related and within a person’s control, such as diet and weight. Others, such as family history and age, are beyond control. Having one or more of these risk factors does not mean that a diagnosis of colorectal cancer is inevitable. However, for people with one rare risk factor, developing colorectal cancer is a near certainty. In less than one percent of all colorectal patients, cancer occurs as a direct result of a condition called familial adenomatous polyposis (FAP).
FAP, caused by an inherited genetic mutation, is diagnosed when someone develops more than 100 polyps in their colon. Polyps found in the colon are typically benign soft tissue growths, which in some cases become cancerous. People with FAP often develop polyps in their mid-teens, and more than 95 percent of people with FAP will have multiple polyps by age 35.
“This disease can lead to a significant risk for developing of early-onset colorectal cancer,” said Sindhu Nair, MD, a board certified hematologist oncologist with Houston Methodist Oncology Partners. “In fact, the high number of polyps involved in classic FAP means that without treatment, people with this condition have nearly a 100 percent chance of developing colorectal cancer.”
Nair said early detection is important for preventing the onset of colorectal cancer. When someone is diagnosed with FAP, it is recommended that close family members undergo genetic testing to determine if they have the condition. This is particularly important for children, who can most benefit from preventive treatment. “We start screening colonoscopies very early, sometimes as early as age 10 or 12,” Nair said.
Treatment often includes a yearly colonoscopy once polyps have been found, but in many cases, these screenings aren’t effective in controlling the high number of polyps. “With FAP, we actually recommend a total proctocolectomy, which is basically the entire removal of the colon,” said Ali Mahmood, MD, board certified colorectal surgeon with Houston Methodist Surgical Associates. “This is because we know the risk of developing colon cancer is going to be very high.”
Surgeons like Mahmood help guide patients through proctocolectomy surgery and recovery. Patients may still need yearly monitoring of their lower intestinal tract if some rectal tissue remains or every one to four years if all rectal tissue has been removed.
For more information about genetic testing for FAP or to schedule an appointment, call 281-274-7500.
Colorectal Cancer Seminar
Join Ali Mahmood, MD, colorectal surgeon, and Leka Gajula, MD, gastroenterologist, to learn more about colorectal cancer — the second leading cause of cancer death for men and women in the United States — and take home a free screening kit on Thursday, March 16th from 6 to 8 pm. Registration is required. Register at events.houstonmethodist.org/sl-colorectal or call 281-274-7500.