ANN ARBOR, Mich. — Colorectal cancer is the second biggest cancer killer, trailing only lung cancer in the number of deaths each year. The American Cancer Societyestimates 51,690 people will die from colorectal cancer this year.
But unlike lung cancer, experts know how to detect who’s at high risk and how to successfully screen for and prevent this disease.
In time for Colorectal Cancer Awareness Month, University of Michigan Comprehensive Cancer Center experts outline genetic counseling, screening and treatment strategies for colorectal cancer.
Genetics pinpoint higher risk About 10 percent of colon cancers can be traced back to genetics. If colon cancer runs in your family, it might be a faulty gene at work. Genetic counseling and testing can help identify people at higher genetic risk of colorectal cancer.
Two common conditions – which can be detected through genetic testing – are linked to colon cancer risk: familial adenomatous polyposis and Lynch syndrome.
“People concerned about a family history of cancer, or those who have been diagnosed with colon cancer before age 50, should talk to their doctor about the possible benefits of genetic counseling,” says Elena Stoffel, M.D., director of the Cancer Genetics Clinic at the U-M Comprehensive Cancer Center.
Genetic counseling typically involves an overview of cancer genetics, a history and physical examination to look for signs and symptoms of familial cancer, and individualized counseling about strategies to lower the risk of cancer.
In Michigan, Gov. Rick Snyder has declared March 22 Lynch Syndrome Hereditary Cancer Awareness Day. About 25,000 people in Michigan are estimated to have Lynch syndrome, a hereditary condition associated with a high risk for developing colorectal and other types of cancer. Most of those at risk remain undiagnosed. For families with multiple cases of colorectal cancer, genetic evaluation can help determine if specialized screening would be beneficial.
Screening = Prevention Colon cancer can be largely prevented through proper screening. Yes, that’s right: prevented.
Colonoscopy, the gold standard in colon cancer screening, can not only detect cancer but also be used to remove precancerous polyps.
“It’s important to be screened routinely for colon cancer, and there are a variety of tests available to help do that. If we reached full compliance with colon cancer screening, we could prevent more than 90 percent of colon cancers,” says D. Kim Turgeon, M.D., associate professor of gastroenterology at the U-M Medical School.
Screening for colon cancer should begin at age 50 for people of average risk. Those with certain risk factors (including genetic predisposition) may need to begin screening earlier.
Treatments improving Unfortunately, only about half of people who should get screened for colorectal cancer do. And so 143,460 people will be diagnosed with the disease this year, according to the American Cancer Society.
Researchers are working to find better ways to treat colorectal cancer. At U-M, radiation oncologists have developed new techniques to treat tumors that spread to the liver. Better surgical techniques allow advanced disease to be surgically removed.
New drugs are also in the pipeline to treat colorectal cancer, most targeting molecular pathways involved in fueling the disease. In addition, researchers are working on tools to help determine who needs chemotherapy and who doesn’t.
“We are using molecular tests to better characterize tumors and tell which patients are most likely to relapse. These tests are especially important for patients with stage II disease where the benefits of chemotherapy may be marginal. If we can tell which patients have a very low risk of recurrence, we can potentially spare them from chemotherapy and it side effects,” says Marwan Fakih, M.D., co-director of the Gastrointestinal Oncology Program at the U-M Comprehensive Cancer Center.
“Molecular characterization is also helpful in determining the best chemotherapy regimen for patients with more advanced disease,” Fakih adds.
For more information about colorectal cancer, including the Cancer Genetics Clinic, colonoscopy screening, the Colorectal Cancer Clinic and clinical trials opportunities, contact the U-M Cancer AnswerLine at 800-865-1125 or visitwww.mcancer.org .