We can test genes for mutations that cause hereditary cancer syndromes using blood, saliva, or skin samples. These samples can typically be obtained on the same day as a Clinical Genetics Service (CGS) consultation in one of the MSK labs. Occasionally, testing may also involve cancer or polyp tissue taken during a previous biopsy or surgery. Genetic testing often is first performed in a member of the family who currently has or has had cancer. If a genetic mutation is found in that person, family members can consider being tested for the same mutation. Some cancers may be caused by mutations in one of several genes. We can test for related cancer genes one at a time, or we can test for them all at the same time. Testing multiple genes at once is called multigene panel testing. A genetic counselor can discuss which genes are included on a given panel test. The panels may occasionally be updated based on new research findings. The results from testing are usually available within a few weeks after the samples are collected and submitted to the laboratory. The specific type of testing, specimen used, laboratory used, and insurance carrier may all contribute to the length of time until the results are available.