*EMBARGOED All research presented at the World Congress of Gastroenterology at ACG2017 is strictly embargoed until Monday, October 16, 2017, at 8:00 am EDT.

Jordan J. Karlitz, MD, FACG, Chair, ACG Public Relations Committee

Poster 1884 Lynch Syndrome Screening: A Nationwide Physician Survey Focusing on Factors Influencing Microsatellite Instability Testing Decisions and Early Onset Colorectal Cancer

Author Insight from Jordan J. Karlitz, MD, FACG, Chair, ACG Public Relations Committee, Tulane Cancer Center

What’s new here and important for clinicians?

Previous studies have demonstrated that screening for Lynch syndrome by analyzing colorectal cancer (CRC) specimens with MSI and/or IHC testing is not routinely performed, even in early-onset CRC patients who may be at highest risk for hereditary syndromes. Our physician survey study seeks to explore factors that may affect Lynch syndrome screening practices. Screening for Lynch syndrome in CRC patients, by MSI and/or IHC and ultimately germline genetic testing, is important for a number of reasons. Identification of Lynch syndrome can affect future colonoscopy intervals (with the potential to prevent future development of CRC), screening for extra-colonic cancers that may be associated with Lynch syndrome, and the extent of colonic resection. It also has important implications for screening family members for Lynch syndrome.

Our study has demonstrated that there does not appear to be a consistent health care provider type ordering MSI/IHC testing. Only 32.7% of respondents felt gastroenterologists should be ordering testing. The majority of survey respondents felt that pathologists should be responsible for testing. Medical oncologists and surgeons were also felt to be responsible, albeit less frequently. Overall, this can contribute to diffusion of responsibility, which may prevent testing from both being consistently performed. It also suggests that if clear testing ordering protocols are developed, this can increase screening rates.

Our survey also demonstrated that providers do not feel that MSI/IHC testing should be routinely performed on colonoscopy biopsy specimens. This can prevent MSI/IHC results, and ultimately germline testing results, from being available preoperatively. This in turn can prevent patients and surgeons from having valuable information that can assist with decisions regarding how much colon is removed in the operating room, which ultimately can affect the risk of developing a second CRC. Guideline familiarity in this situation appeared to cluster in those practicing in urban practice locations and those with a GI oncology specialization. Targeted educational initiatives with a focus on rural areas and centers with less-specialized services may be able to help optimize management strategies. Educational initiatives can also address the issue of lack of familiarity of MSI/IHC test result interpretation, which was also demonstrated to be an impediment to test ordering in our study.

What do patients need to know?

Patients should be aware of the testing options available to identify Lynch syndrome. They should be proactive about discussing screening options with their health care providers in order to assure that screening takes place and takes place at the appropriate time. Currently, national guidelines suggest that all patients with CRC– not just early-onset CRC—should be considered for Lynch syndrome screening. Given that there are approximately 135,000 new cases of CRC diagnosed each year in the United States, this can have enormous implications for both patients and family members.

It should also be noted that patients who do not have CRC themselves, but have a family history of CRC and other cancers, or even a personal history of a non-CRC Lynch syndrome-associated cancer, may need to be considered for genetic counseling and testing.

Read the Abstract

See Figure

Author Contact
Jordan J. Karlitz, MD, FACG, Chair, ACG Public Relations Committee, Tulane Cancer Center

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