Familial adenomatous polyposis 1 (FAP1) is an inherited disorder characterized by cancer of the colon and rectum. People with FAP1 may begin to develop multiple benign polyps in the colon as early as their teenage years. Unless the colon is removed, these polyps will become malignant. The average age at which an individual develops colon cancer in FAP1 is 39 years.
In people with familial adenomatous polyposis 1, the number of polyps increases with age, and hundreds to thousands of polyps can develop in the colon. Also of particular significance are noncancerous growths called desmoid tumors. These fibrous tumors usually occur in the tissue covering the intestines and may be provoked by surgery to remove the colon. Desmoid tumors tend to recur after they are surgically removed. Benign and malignant tumors are sometimes found in other places in the body, including the small intestine, stomach, bones, skin, and other tissues. People who have colon polyps as well as growths outside the colon are sometimes described as having Gardner syndrome.
Mutations in the APC gene cause familial adenomatous polyposis 1. These mutations affect the ability of the cell to maintain normal growth and function. Cell overgrowth resulting from mutations in the APC gene leads to the colon polyps seen in familial adenomatous polyposis. Although most people with mutations in the APC gene will develop colorectal cancer, the number of polyps and the time frame in which they become malignant depend on the location of the mutation in the gene.
Methodology: Sequencing of entire coding region
Purpose: Confirmation of Clinical Diagnosis
ICD-10 code D12.0-D12.6/ K63.5
Test Requisition: Sequencing Requisition
CPT Code: 81201 full gene sequence Cost: $1107.00
CPT Code: 81202 known familial variant Cost: $396.00
Turn-around-time: 3-4 weeks
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