GASTROENTEROLOGY ARTICLE OF THE WEEK
April 27, 2006
Gruber SB. New developments in Lynch Syndrome (Hereditary Nonpolyposis colorectal cancer) and mismatch repair gene testing. Gastroenterology 2006;130:577-87.
1. Which of the following microsatellite instability results is consistent with the Lynch Syndrome
a. MSI stable
b. MSI low
c. MSI high
d. out of orbit satellite
2. For patients with the Lynch Syndrome:
a. Lifetime risk for colon cancer is over 50%
b. Endometrial cancer risk is over 40%
c. Risk of ovarian cancer is about 10%
d. risk of gastric cancer is markedly increased in the US
True or False
3. Breast cancer is one of the HNPCC associated cancers
4. Microsatellite instability is the hallmark of defective mismatch repair
5. Patients with family history suggestive of Lynch Syndrome but who are negative for DNA mismatch repair gene defect have a lower incidence of endometrial and colon cancer compared to those with a defective mismatch repair gene
6. The two most common mutations in Lynch Syndrome are hMLH1 and hMSH6
7. Features that may be found in a colon tumor that are suggestive of Lynch syndrome include tumor infiltrating lymphocytes, mucinous/signet ring differentiation and medullary growth pattern.
8. Genetic testing for Lynch syndrome has been clinically available for over 10 years but our Genetics department has not heard about it yet…
9. Microsatellite instability testing should be considered for individuals with colon cancer developing before age 50
10. Immunohistochemical staining in tumor tissue can be used to determine the mismatch repair gene defect present in a particular individual