Expert Diagnosis and Treatment for Hereditary Colorectal Cancers

Familial Adenomatous Polyposis (FAP) is rare inherited condition caused by a mutation in the APC gene - a gene designed to suppress tumor growth. FAP causes polyps to develop in the colon and rectum, usually before age 20. While some patients have dozens of polyps, others may develop hundreds to thousands of polyps. The risk of colorectal cancer for people with FAP is very high (nearly 100 percent) and it often occurs at an early age. Even though it is inherited, up to 1 out of 4 patients do not have a family history of FAP and patients who have FAP have a 50 percent chance of passing it on to their children.

Patients with FAP have other risks, besides colorectal cancer. These include benign (non-cancerous) conditions like bone tumors (osteomas), soft tissue tumors (epidermoid cysts and fibromas), extra teeth or unerupted teeth and benign polyps in the stomach. There is also a risk of desmoid tumors - benign tumors that can grow inside or outside of the abdomen and can be difficult to remove. There are also increased risks of other cancers, including intestinal, pancreatic, thyroid, brain and stomach.

If your doctor thinks that you may have FAP based on the number of polyps you have, or if anyone else in your family is diagnosed with FAP, counseling and testing by the UH Medical Genetics Department may be recommended. Patients with FAP need a variety of ongoing tests for screening and surveillance. If there are too many polyps or they are growing too quickly to be controlled by colonoscopy, surgery to remove the colon and rectum may be recommended.

Lynch Syndrome, sometimes called HNPCC (Hereditary Non-Polyposis Colon Cancer), is an inherited condition that leads to an increased risk of colorectal and other cancers. It is relatively common - approximately 1 in 300 people in the U.S. have Lynch Syndrome and it is responsible for about 3 percent of colon cancers.

Lynch Syndrome is caused by a genetic change in one of four genes called mismatch repair (MMR) genes. It is usually inherited from a parent with Lynch Syndrome and there is a 50 percent chance of passing it on to each child. Because not everyone with Lynch Syndrome gets cancer, it can sometimes be hard to diagnose based on family history alone. The colon cancers caused by Lynch Syndrome tend to occur at earlier ages, on the right side of the colon, and grow more quickly than those seen in the general population. Also, after having one colorectal cancer a person with Lynch Syndrome is more likely to experience recurring cancer.

In addition to developing colorectal polyps/cancer earlier in life, patients with Lynch Syndrome are more likely to develop other cancers including endometrial (uterine), ovarian, stomach, urinary tract, small intestine, pancreas/liver, brain and skin.

Patients with Lynch Syndrome should have colonoscopies starting at an earlier age and have them more frequently than other patients. They should also have screenings and surveillance for other cancers. At University Hospitals, all biopsies of colorectal cancer and endometrial cancer are screened for Lynch Syndrome. If there is a concern based on this or on family history, patients can be seen in the UH Medical Genetics Department for further counseling and testing.

MYH-Associated Polyposis is an inherited condition that leads to an increased risk of colorectal polyps and cancer. It usually occurs in people 40-60 years of age and most patients with this syndrome have between 10 and 100 polyps.

MAP is caused by a genetic change in the MUTYH gene. People with MAP have inherited two mutated copies of the gene, one from each parent. People who inherit just one copy of the mutated gene from one parent, do not have MAP but are at a slightly increased risk of colorectal cancer and could pass on the mutation to their children.

Patients with MAP are at increased risk of colorectal cancer. In addition, patients with MAP may have an increased risk of developing polyps and cancer in their stomach and small bowel and may be at higher risk for thyroid cancer. Patients with MAP should have colonoscopies and other tests more frequently than other patients.

If your doctor thinks that you may have MAP based on the number of polyps you have, or if anyone else in your family is diagnosed with MAP, counseling and testing by the UH Medical Genetics Department may be recommended.

Also called hyperplastic polyposis syndrome, the exact cause of Serrated Polyposis Syndrome is unknown but experts believe it is an inherited condition. This condition causes patients to develop serrated (jagged or saw-edged) polyps in the colon or rectum. It is important to note that not all patients with serrated polyp(s) have this syndrome as most serrated polyps are not related to a genetic cause. If a diagnosis of SPS is confirmed, however, patients are at increased risk for colorectal cancer and will require more frequent colonoscopies.

If your doctor thinks that you may have serrated polyposis syndrome based on the number of polyps you have, or if anyone else in your family is diagnosed with it, counseling and testing by the UH Medical Genetics Department may be recommended.

Juvenile Polyposis Syndrome is an inherited condition in which non-cancerous polyps or growths called hamartomas develop in the intestines. Even though hamartomas are noncancerous, patients diagnosed with JPS are at increased risk for cancers of the stomach, pancreas, small intestine, colon and rectum. Although the name “juvenile polyposis” is due to the type of polyp, not the age of the patient, this syndrome does typically occur in younger patients, usually in their teens or early 20s.

JPS is diagnosed either by the presence of five or more juvenile polyps in the colon and rectum, multiple juvenile polyps throughout the intestines or by family history. Although there are two different genes that are linked to JPS - BMPR1A and SMAD4 - not all patients or their family members will have identifiable changes in these genes. Those patients who are identified as having SMAD4 mutations are at risk for Hereditary Hemorrhagic Telangiectasia (HHT), which can cause nosebleeds, aneurysms and arteriovenous malformations.

Patients with JPS need a variety of tests for screening and surveillance because of their increased cancer risk. If your doctor thinks that you may have JPS, or if anyone else in your family is diagnosed with it, counseling and testing by the UH Medical Genetics Department may be recommended.

Peutz-Jeghers syndrome is an inherited condition in which non-cancerous polyps or growths called hamartomas develop in the small and large intestine and may cause bleeding or intestinal blockage, usually in childhood. Even though hamartomas are noncancerous, patients diagnosed with PJS are at increased risk for cancers of the breast, colon and rectum, pancreas, stomach, testicles, ovaries, lung, cervix and others.

Some people with PJS will develop areas of pigmentation (darkening of the skin) around the mouth, lips, fingers or toes called mucocutaneous pigmentation. These usually occur in childhood and can fade with age.

Patients with PJS need a variety of tests for screening and surveillance because of their increased cancer risk. If your doctor thinks that you may have PJS, or if anyone else in your family is diagnosed with it (about half of patients with PJS will have a family history of the syndrome), counseling and testing by the UH Medical Genetics Department may be recommended.