Hereditary nonpolyposis colon cancer (HNPCC) is caused by a mutation in any of five genes. HNPCC is an inherited condition, so if you have it, you were born with it. Approximately 2-5% of colon cancer is caused by HNPCC.
What are the effects of HNPCC?Most people have about a 6% chance of developing colon cancer at some point in their lives, usually after age 60. People with HNPCC have about an 80% risk of developing colon cancer, usually by age 44. Women with HNPCC also have about a 50% chance of developing uterine cancer.
It's important to note that HNPCC isn't a form of colon cancer. HNPCC is simply a genetic mutation that increases a person's chances of developing colon cancer, like the BRCA mutations and breast cancer.
What do you do about HNPCC?A typical screening recommendation for people at average risk for colon cancer is to get their first colonoscopy at age 50 and if all is well, have a follow-up colonoscopy in ten years. Since they're in a high-risk category, people with HNPCC are encouraged to have their first colonoscopy at age 20, with follow-up colonoscopies every year or two.
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- Hereditary Non-polyposis Colorectal Cancer. Cleveland Clinic. 29 Oct. 2003. 1 Sep. 2006 [http://www.clevelandclinic.org/registries/inherited/hnpcc.htm].
- Komaromy, M. What is HNPCC? Genetic Health. 11 Aug. 2000. 1 Sep. 2006 [http://www.genetichealth.com/CRC_HNPCC_A_Hereditary_Syndrome.shtml].