Familial adenomatous polyposis is a disorder of the large intestine that leads to the growth of hundreds of tiny precancerous masses called polyps. It is an inherited condition that usually emerges in adolescence and becomes cancerous in the third or fourth decade of life. When doctors are aware that a person has familial adenomatous polyposis, they usually schedule yearly screenings early in life to track changes and assess symptoms. Surgery to remove part or all of the colon is eventually necessary in almost all cases to prevent the development of cancer.
Medical researchers have determined that the condition stems from a mutation of the adenomatosis polyposis coli (ATC) gene. A mutated gene is unable to produce particular proteins that help regulate normal rates of cell division. The disorder is autosomal dominant, meaning that a child can inherit it if either of his or her parents carries an abnormal ATC gene.
Most people who have familial adenomatous polyposis do not experience adverse physical symptoms until their condition turns cancerous. The clusters of precancerous polyps are usually very small, and do not disrupt normal bowel functioning. Some individuals do experience occasional bouts of abdominal pain, diarrhea, or rectal bleeding if polyps irritate surrounding tissue. If polyps go untreated into adulthood, colon or rectal cancer can cause severe gastrointestinal problems and potentially spread to other parts of the body.
Doctors do not normally treat familial adenomatous polyposis until a patient is in his or her late teens or 20's, after the gastrointestinal tract and immune system have had time to fully develop. Since nearly every case eventually turns cancerous, specialists usually decide to perform preventive surgery. Depending on the location of polyps, a surgeon may remove only a section of the colon or the entire colorectal structure. Advancements in medical technology allow surgeons to conduct colectomy procedures efficiently, accurately, and with minimal impact on patients' future gastrointestinal functioning.
Familial adenomatous polyposis is a very persistent condition, and it is likely that polyps will still form somewhere along the colon even after surgery. Any new polyps that form, however, can typically be discovered and removed before they turn cancerous. Patients who have the condition need to attend regular medical checkups throughout their lives in order to ensure their gastrointestinal health. Individuals who want to have children are encouraged to seek genetic counseling services to learn about the risks of passing on the condition to offspring.