Dr Leo J. Schouten
Dept of Epidemiology, GROW - School for Oncology & Developmental Biology
University of Maastricht
Maastricht, The Netherlands
Project 1 title
Nutritional and Lifestyle Characteristics of Vegetarian and Very Low Meat Diets as Determinants of Subsequent Cancer Risk (2009/11)
Project 2 title
A prospective study of diet and the risk of Head-Neck Cancer (2010/253)
Scientific abstract 1
The importance of following a vegetarian or very low meat diet compared to a diet including meat is not clear in relation to cancer risk. This might be due to many other dietary and lifestyle factors differing between vegetarians and meat consumers.
This study will investigate whether and how diet and lifestyle differ between vegetarians and meat consumers, whether these groups differ in cancer risk and whether the results depend on the time since adoption of a vegetarian diet. Taking the ongoing Netherlands cohort study on diet and cancer (NLCS), which was initiated in 1986 among 120,852 men and women aged 55-69 years who completed a comprehensive questionnaire on dietary habits and lifestyle, data will be analysed from a subgroup comprising 8,500 randomly selected subjects and 3,000 vegetarians and very low meat consumers. Cancers that will be investigated include total, colorectal, lung, prostate and breast cancer. The findings of this study will provide useful tools to develop and fine-tune cancer prevention strategies.
Scientific abstract 2
Background: Several studies on diet and the risk of head-neck cancer (HNC) have been conducted, mainly case-control studies and only very few prospective cohort studies. Smoking and alcohol consumption are important risk factors, but there is considerable evidence to suggest that diet is also related to HNC risk. Overall, results are still inconclusive, mainly because evidence from prospective studies is very scarce.
Objectives: In the proposed study various hypotheses regarding diet (intake of vegetables, fruits, carotenoids, vitamins, fat and meat), toenail selenium status and anthropometry (including life-course exposures) and HNC risk will be tested. Effect modification of the dietary risk factors and HNC risk by smoking and alcohol consumption will be investigated.
Setting & Methods: This study will be executed within the ongoing Netherlands Cohort Study on Diet and Cancer (NLCS). At baseline in 1986, 120,852 men and women aged 55-69 years completed a self-administered questionnaire, including a semi-quantitative food frequency questionnaire with 150 questions on food. Selenium status will be investigated by instrumental neutron activation analysis using toenail clippings that were also collected at baseline.
Cancer follow-up was established by annual record linkages with the Netherlands cancer registry, the nationwide pathology registry and the cause of death registry. After 20.3 years of follow-up about 445 cases of squamous cell HNC will be available for analysis, using the case-cohort methodology. Rate ratios will be adjusted for possible confounders like cigarette smoking and alcohol consumption. Associations will be studied for HNC overall and for the subtypes oral cavity cancer, oropharyngeal & hypopharyngeal cancer and laryngeal cancer.
Impact: This study will contribute significantly to the scientific evidence regarding the association of food and the risk of (subtypes of) HNC.
Project 1 plain language abstract
Background: The importance of following a vegetarian or very low meat diet compared to a diet including meat is not clear in relation to cancer risk. This might be due to many other dietary and lifestyle factors differing between vegetarians and meat consumers.
Project Details: This study will investigate whether and how diet and lifestyle differ between vegetarians and meat consumers, whether these groups differ in cancer risk and whether the results depend on the time since adoption of a vegetarian diet. Taking the ongoing Netherlands cohort study on diet and cancer (NLCS), which was initiated in 1986 among 120,852 men and women aged 55-69 years who completed a comprehensive questionnaire on dietary habits and lifestyle, data will be analysed from a subgroup comprising 8,500 randomly selected subjects and 3,000 vegetarians and very low meat consumers. Cancers that will be investigated include total, colorectal, lung, prostate and breast cancer. The findings of this study will provide useful tools to develop and fine-tune cancer prevention strategies.
Project 2 plain language abstract
Title: A prospective study of diet and the risk of head and neck cancer.
Background: Several studies on diet and the risk of head-neck cancer (HNC) have been conducted, mainly case-control studies and only very few prospective cohort studies. Results from prospective cohort studies are generally considered to be more reliable because information on the exposure, i.e. diet, is collected before the event. Smoking and alcohol consumption are important risk factors of HNC, but there is considerable evidence to suggest that diet is also related to HNC risk. Overall, results are still inconclusive, mainly because evidence from prospective studies is very scarce.
Aims & goals: In the proposed study various hypotheses regarding diet (intake of vegetables, fruits, carotenoids, vitamins, fat and meat), toenail selenium status and anthropometry (including life-course exposures) and HNC risk will be tested. It will also be investigated whether the association between diet and HNC risk is different in smokers and non-smokers and in drinkers and non-drinkers of alcohol.
How it will be done: This study will be executed within the ongoing Netherlands Cohort Study on Diet and Cancer (NLCS). This study was started in 1986 with the inclusion of 120,852 men and women aged 55-69 years. The participants completed a self-administered questionnaire at baseline, including 150 questions on food and other questions on smoking, alcohol, occupation, physical activity, etc. Selenium status will be investigated using toenail clippings that were also collected at baseline. Cancer follow-up was established by annual record linkage with the Netherlands cancer registry, the nationwide pathology registry and the cause of death registry. After 20.3 years of follow-up (from 1986 until 2006) about 445 cases of squamous cell HNC will be available for analysis. Analyses will be adjusted for possible confounders, like cigarette smoking, alcohol consumption, etcetera. Associations will be studied for HNC overall and for the subtypes mouth, pharynx and larynx cancer.
Potential impact: This study will contribute significantly to the scientific evidence regarding the association of food and the risk of (subtypes of) HNC. This evidence can be used to establish guidelines for HNC prevention.
| Institution and location | Degree | Year | Scientific Field |
|---|---|---|---|
| Medical School Maastricht University, The Netherlands | MD | 1981 | Medicine |
| Nijmegen University, The Netherlands | PhD | 1996 | Cancer Epidemiology |
| 2009 - present | Programme leader programme ´Cancer Epidemiology and Prevention within the GROW-School for Oncology and Developmental Biology |
| 2006 - present | Associate professor, Department of Epidemiology, Maastricht University |
| 2000 - 2006 | Assistant professor, Department of Epidemiology, Maastricht University |
| 1993 - 1996 | Researcher, Department of Epidemiology, Nijmegen University |
| 1983 - 2000 | Head of Cancer Registry, Comprehensive Cancer Centre Limburg, Maastricht |
| 1981 - 1983 | Military service |
Research interests
Cancer epidemiology, ovarian cancer, renal cell cancer, endometrial cancer, oesophageal cancer.
Left to right: Dr. Bernd Kremer, Denise Maasland (PhD student), Dr. Piet van den Brandt and Dr. Leo J. Schouten