Colon and rectal cancers are often referred to as “colorectal cancer.”
FAP can be diagnosed when you have more than 100 benign (noncancerous) growths calledpolypsor colorectal adenomas.
It eventually causes hundreds to thousands of such growths in the colon and rectum.
Illustration by JR Bee, Verywell
FAP is responsible for about .5% of the total number of colon cancer cases in general.
FAP is also known as:
Genetics and Timelines
FAP is an autosomal dominant disease.
That means someone with the condition has one copy of a mutated gene and one normal copy.
In an affected person, polyps can start forming in the teenage years.
If they go untreated, the polyps may become cancerous.
The average age for someone with FAP to develop cancer is 39 years old.
Some cases of FAP are classified as “attenuated FAP.”
Adenomatous Polyps
The polyps in FAP are referred to as “adenomatous.
“Adenomatous polypsstart out as benign but eventually change into being cancerous (malignant).
For this reason, they are often referred to as pre-cancerous.
These polyps start developing in the person at around 16 years of age.
The APC gene is responsible for the production of the APC protein.
This APC protein is, in turn, responsible for controlling how frequently cells divide.
Basically, it suppresses cell division so they don’t divide too fast or uncontrollably.
When there’s a mutation in the APC gene, there tends to be an overgrowth in cells.
This is what causes the numerous polyps in FAP to form.
There is another pop in of FAP called autosomal recessive familial adenomatous polyposis.
This punch in of FAP is also called MYH-associated polyposis.
Risk Factors
Having first degree relatives with FAP is the main risk factor for developing the disease.
Some people have no family history, however, and the disease is attributed to random gene mutaions.
Screening for people at risk of having FAP usually starts at 10 to 12 years of age.
For those believed to be at risk for attenuated FAP, screening usually starts in the teenage years.
Diagnosis
Many different tests and procedures are used to diagnose FAP.
Colon examination can be done in many ways.
You will also be required to clear out your bowels using laxatives or an enema.
Usually, sedatives are given before the procedure is started.
Undergoingthis testcan cause discomfort and even sometimes pain.
However, it is the best way to detect colon polyps as well as colon cancer.
The healthcare provider may also take out polyps tissue (biopsy) during the colonoscopy for further testing.
Sigmoidoscopy is sometimes called flexible sigmoidoscopy.
CT Colonography
This test involves using aCT scanto obtain clear and detailed images of the colon and rectum.
The healthcare provider will then be able to identify whether there is the presence of polyps.
The bowels must be completely cleaned out and prepped for clear and optimum image quality to be obtained.
(Sedatives are not needed for this.)
It’s also called a CTC, virtual colonoscopy (VC), or CT Pneumocolon.
Barium Enema
This a key in of X-ray of the colon.
This method of diagnosis is no longer really used as frequently as the other methods.
They are also recommended when a family history of FAP is present.
Treatment
Once FAP is diagnosed, it must be treated.
Otherwise, it will progress into colorectal cancer.
Eventually, however, there will be too many polyps for this to be effective.
Surgery
If the polyps cannot be removed individually, the next course of action is surgery.
A variety of different surgeries are available.
Colectomy and Ileorectal Anastomosis
Acolectomyinvolves removing the entirety of the colon but leaving part of the rectum untouched.
The part of the rectum that is left will then be surgically connected to the small intestine.
Colectomy andIleostomy
In this procedure, your entire colon and rectum are removed.
This surgery is sometimes temporary, although in other cases, the bag may remain to collect waste.
Restorative Proctocolectomy
This involves removing the entirety of the colon and most or all of the rectum.
This way, waste can be stored in this pouch and your bowel function is preserved.
Medication
Medication is sometimes additionally prescribed to treat FAP.
While the aim of surgery is to remove the polyps, surgery does not in itself cure the condition.
Sulindac is not yet approved by the FDA in the treatment of FAP.
Despite this, it is widely and commonly used.
Another arthritis drug exists called Celecoxib, which is FDA approved.
It reduces the number of polyps in the colon and rectum.
These polyps and tumors, especially the ones with the propensity to become cancerous, should be surgically removed.
However, they still need to be monitored.
Coping
Surgery doesnt cure the FAP and polyps may still continue to grow.
They are used to screen for extra-colonic malignancies.
Additionally, your healthcare provider may recommend genetic counseling.
It is highly recommended for people who have FAP and their relatives.
It can also help them emotionally support their loved one with FAP.
However, with the right treatment and monitoring plan, youll be able to successfully navigate this condition.
This way you could determine the risk to future children and evaluate your options.
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Children’s Hospital of Philadelphia.Familial adenomatous polyposis.
Waller A, Findeis S, Lee MJ.Familial adenomatous polyposis.J Pediatr Genet.
2016;5(2):78-83. doi:10.1055/s-0036-1579760
Ambry Genetics.Familial adenomatous polyposis.
Johns Hopkins Medicine.Familial adenomatous polyposis treatment.
Cleveland Clinic.Familial adenomatous polyposis (FAP).
