Dr. Sapna Syngal from the Dana-Farber Cancer Center in Boston presented on hereditary colorectal cancer syndromes. These syndromes elevate the risk for colorectal cancer, and if they are not recognized, their associated cancers present with a young age of onset. Patients and potential patients need to be referred for genetic counseling and testing, particularly those who present at a young age, have a high number of polyps, show upper GI lesions, and have strong family history of cancer or polyps. Dr. Syngal highlighted the issue of "genetic malpractice" that is growing in the United States due to a lack of recognition and referral for evaluation. These syndromes are managed much differently than sporadic cancer in their approach to surgery, surveillance for associated cancers, the screening of family members, and reproductive counseling and prenatal testing.
Dr. Syngal reviewed familial adenomatous polyposis (FAP), an autosomal dominant condition, and highlighted MYH associated polyposis (MAP), an autosomal recessive condition. Both FAP and MAP can present with colon polyps and cancer, upper GI lesions, form desmoid tumors, and are associated with thyroid, brain, and osteoma tumors. Care is through colectomy, upper GI surveillance, and chemoprevention for any lower GI remnant. Dr. Syngal also highlighted Lynch syndrome, which is associated with tumors of the colon and upper GI track, female reproductive track, urinary track, and sebaceous skin tumors. Lynch syndrome patients can undergo colonoscopic surveillance and subsequent colectomy, as well as endometrial aspiration and subsequent total abdominal hysterectomy-bilateral salpingo-oophorectomy. Dr. Syngal reviewed testing of tumors for microsatellite instability and immunohistochemistry for the DNA mismatch repair genes (mutation of which cause Lynch syndrome) and discussed prediction models for germline testing.
John M. Carethers, M.D., is the John G. Searle Professor and chair of the department of internal medicine at the University of Michigan, Ann Arbor.
