Awareness of Genetic Testing for Colorectal Cancer Predisposition Among Specialists in Gastroenterology Shivani Batra, M.S., Heiddis Valdimarsdottir, Ph.D., Margaret McGovern, M.D., Ph.D., Steven Itzkowitz, M.D., and Karen Brown, M.S., C.G.C. Departments of Human Genetics, Cancer Prevention and Control, and Medicine, Mount Sinai School of Medicine, New York, New York OBJECTIVES: Adult gastroenterologists practicing in New York State were surveyed to determine their practice with regard to identifying family histories consistent with inher- ited forms of colorectal cancer, and to assess their awareness of cancer genetic counseling and molecular genetic testing for familial adenomatous polyposis (FAP) and hereditary nonpolyposis colorectal cancer (HNPCC). METHODS: A closed-ended questionnaire was mailed to 815 gastroenterologists identified through the membership Di- rectory of the American Gastroenterological Association (1998). Two mailings resulted in a response rate of 35%. RESULTS: In all, 99% of the gastroenterologists obtained a family history from their patients, and 95% were aware of cancer genetic counseling. However, only 51% would rou- tinely refer patients for genetic counseling before providing cancer predisposition testing. In addition, only 52% were aware of the availability of genetic tests for FAP and 34% for HNPCC. Presented with a family history consistent with HNPCC, 79% could identify the syndrome, 26% recom- mended genetic counseling for the consultand, and 16% advised appropriate screening, according to current recom- mendations. CONCLUSIONS: The majority of gastroenterologists do ob- tain a family history on their patients. However, there is a need for physician education regarding the recognition of pedigrees consistent with inherited colorectal cancer, the genetic counseling process, and the availability of mutation testing for FAP and HNPCC. (Am J Gastroenterol 2002;97: 729 –733. © 2002 by Am. Coll. of Gastroenterology) INTRODUCTION Colorectal cancer (CRC) is the second most common cause of cancer deaths in the United States, with a lifetime risk of developing CRC estimated at 5– 6%. Because approxi- mately 10 –20% of CRC cases are familial, identification of individuals at risk is an important public health issue. A subset of familial CRC cases is caused by the hereditary syndromes familial adenomatous polyposis (FAP) and he- reditary nonpolyposis colorectal cancer (HNPCC). Specific germline mutations associated with both disorders have been identified. Tests for these mutations in individuals at risk may guide future screening and assist in prevention of disease. Familial adenomatous polyposis is an autosomal domi- nant disorder caused by mutations in the APC (adenomatous polyposis coli) gene. About one third of cases are the result of de novo germline mutations in the absence of any family history of the disease. Patients typically present with hun- dreds to thousands of adenomatous polyps throughout the large intestine. These benign polyps develop between the ages of 10 and 20 yr. Because it is virtually 100% penetrant, nearly all persons with FAP will have adenomas by age 40 yr and, if left untreated, cancer of the colon by age 50 yr (1). Hereditary nonpolyposis colorectal cancer is an autoso- mal dominant disorder with a lifetime risk for developing CRC of about 70 – 80%. It is caused by germline mutations in one of at least five known DNA mismatch repair genes. Affected individuals generally develop colorectal cancer 20 –25 yr earlier than the general population. Unlike the florid polyposis seen in FAP, HNPCC is associated with the development of only a few polyps; nonetheless, these polyps may progress more rapidly from adenoma to carcinoma (2). Thus, cancers occurring in the context of HNPCC may be difficult to distinguish from sporadic cancers. To promote consistency in recognizing high risk individ- uals, a set of guidelines known as the Amsterdam Criteria was developed in 1991 by the International Collaborative Group on HNPCC. They are as follows: 1) at least three members of the family have CRC (FAP excluded), one of whom is a first-degree relative of the other two; 2) two or more generations are affected; and 3) at least one relative was diagnosed before age 50 yr. More recently, it has been suggested that these criteria are too restrictive, as patients with identified HNPCC mutations have been reported who do not meet these criteria. A new set of criteria was pro- posed to also take into account the extracolonic cancers associated with HNPCC. With these criteria known as Am- sterdam II, in addition to CRC, family members may be THE AMERICAN JOURNAL OF GASTROENTEROLOGY Vol. 97, No. 3, 2002 © 2002 by Am. Coll. of Gastroenterology ISSN 0002-9270/02/$22.00 Published by Elsevier Science Inc. PII S0002-9270(01)04118-1