Please can you give a brief introduction to Lynch syndrome?
Lynch syndrome is one of the inherited cancer syndromes characterized by the development of colorectal cancer, endometrial cancer and other cancers at an early age.
How young do Lynch syndrome patients tend to be?
Colorectal cancer in those with Lynch Syndrome often occur before age 50, which is significantly lower than the age at which colorectal cancer occurs in the population at large (~65 years).
How many people does Lynch syndrome affect?
Around 1-3% of all colorectal cancers are due to Lynch Syndrome.
What are the main symptoms of Lynch syndrome?
Individuals with Lynch Syndrome have an especially a high risk for large bowel (colorectal cancer) cancer as well as cancer of the endometrium, stomach, small bowel, upper urinary tract, ovaries and the brain.
Do individuals with Lynch syndrome have any other symptoms?
Besides the symptoms associated with the presence of tumors (e.g. colorectal bleeding, weakness, abdominal pain etc.) no other symptoms are described among those with Lynch Syndrome.
How is Lynch syndrome diagnosed?
By a genetic test.
What is known about the causes of Lynch syndrome?
Inherited mutations in genes involved in mismatch repair are responsible for the high cancer risks in Lynch Syndrome.
Which genes are responsible for Lynch syndrome?
The most commonly mutated mismatch repair genes in Lynch Syndrome are MLH1 and MSH2. Mutations may also occur in MSH6, PMS2 and other genes, but this is less common.
How did your research into the consumption of snack foods and the risk of colorectal cancer in individuals with Lynch syndrome originate?
There is convincing evidence that overweight and lifestyle, including dietary habits influence the risk of colorectal cancer in the general population, i.e. among those with no inherited high risk of cancer.
Our previous studies among individuals with the Lynch Syndrome showed that overweight and smoking also substantially increased their risk of colorectal cancer.
This study was the next step to see whether these people with a very high risk of cancer may be able to do something to decrease this risk by altering their lifestyle habits, including their diet.
What did your research involve?
We examined dietary patterns and colorectal adenoma (a precancerous lesion) risk among 486 mutation carriers with the Lynch Syndrome in a prospective cohort study.
Were the dietary patterns of the mutation carriers gathered via personal diaries? How did you make sure that this information was reliable?
We used a self-administered, validated, 183 item food frequency questionnaire to assess habitual dietary habits of the participants.
How did you measure colorectal adenoma risk in the carriers?
Colonoscopy follow-up data was collected at the Lynch Syndrome family registry at the Netherlands Foundation for Hereditary Tumors and from medical records.
Also, information about all previously performed colonoscopies, surgical interventions, and cancer and adenoma occurrences was gathered.
For each colonoscopy, information on number of neoplasms, plus location, size, and histology of these was collected.
What did your research find?
After a median follow-up time of 20 months, specific dietary patterns appeared to be associated with colorectal adenoma occurrence in these individuals at high risk of colorectal cancer.
The observed patterns influencing the risk are comparable to those influencing colorectal cancer risk in the population at large. Especially, a dietary pattern which we named the Snack pattern, i.e. high in chips, fried snacks, fast food snacks, cooking fat, butter, sweets and sodas increased the risk of colorectal adenomas about two fold.
An increased risk (although not statistically significant) was also observed for those with a pattern high in meat.
Did your research look at the impact of a diet high in processed meat?
Processed meat was part of the pattern high in meat, but we did not specifically look at processed meat yet.
What are your thoughts on the recent research by Rohrmann, Overvad et al. on meat consumption and mortality that was published in the BMC Medicine?
The association between red meat, processed meat and colorectal cancer risk has been shown in several studies. The publication by Rohrmann et al based on results of the EPIC study confirms that especially processed meat is related to increased cancer mortality and death due to cardiovascular disease.
What impact do you think your research will have?
This research shows that among those with an inherited very high risk of cancer, what you eat may still be important.
This has an important impact on how we think about inherited diseases and it may influence the lifestyle of those at high risk.
What are your plans for future research in this field?
The next step in this research will be to recruit more individuals with this syndrome (possibly internationally) and to collect blood samples from the participants. The blood samples will for instance enable us to assess certain vitamins and other nutrients and evaluate whether these are related to risk.
Where can readers find more information?
Please email [email protected]
About Prof. Ellen Kampman
Ellen Kampman is a nutritional epidemiologist and professor in Diet and Cancer at Wageningen University and Research Center in the Netherlands.
She also holds an endowed chair at the VU University Amsterdam, the Netherlands on behalf of the Alpe D'Huzes foundation.
She received post-doctoral training at the Fred Hutchinson Cancer Research Centre in Seattle and the Harvard School of Public Health in Boston, USA.
Her research focus is on the role of diet and other lifestyle factors in cancer prevention as well as cancer progression and survival.
She received grants from national and international funding agencies in collaboration with oncologists, gastro-enterologists, nutritionists, molecular biologists, pathologists and toxicologists.
She is senior editor of the peer-reviewed AACR journal ‘Cancer Epidemiology Biomarkers and Prevention’.
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