Symposium 6 Part ll BAPEN Medical/Nutrition iti Society Nutritional Science in Cancer
Food, Nutrition, Physical Activity, and the Prevention of Cancer: a Global Perspective Professor Martin Wiseman FRCP FRCPath Project Director, WCRF International University of Southampton
WCRF GLOBAL NETWORK AICR WCRF UK WCRF FR WCRF INTERNATIONAL ASSOCIATION WCRF NL WCRF HK
CAUSE SPECIFIC MORTALITY ENGLAND 2000 ACCIDENTS 2% RESPIRATORY 10% OTHER 20% CVD 40% ACCIDENTS 2% OTHER 24% RESPIRATORY 11% CVD 40% CANCER 28% CANCER 24% MALE FEMALE Dept of Health, 2000
Estimated Numbers of New Cancer Cases (Incidence) and Deaths (Mortality) in 2002 Parkin, D. M. et al. CA Cancer J Clin 2005;55:74-108. Copyright 2005 American Cancer Society
MISSION
Underlying principles 1. Identify causal exposures - protective or adverse 2. Examine all relevant evidence 3. Use most robust methods 4. Transparency
Inferring causality 1. Strength 2. Consistency 3. Specificity 4. Timing 5. Dose Response 6. Plausibility 7. Coherence 8. Experiment 9. Analogy Bradford Hill
EXPERT REPORT PROCESS Peer Reviewers Review protocol and end product developed by SLR centres SECOND EXPERT REPORT Methodology Task Force Develop methodology to be used din reviews STAGE 1 Systematic Literature Review Centres Perform review on link between diet, physical activity, nutrition and cancer Panel Interpretation of the evidence STAGE 2 STAGE 3 Advisory Group Guidance and feedback to SLR centres and to Executive Team
Systematic reviews e 1. Expert international Task Force for method 2. Seven centres - USA, UK, NL, Italy 3. SLR centre coordinator 4. Test of reproducibility 5. Standardised search, analysis and display 6. Epidemiology and mechanisms 7. Quality assessment 8. Peer review - protocol, report 9. Defined expertise required Nutrition, epidemiology, systematic review, cancer biology, statistics
17 Cancer Sites Food, Nutrition, and Physical Activity Mouth, pharynx, larynx Nasopharaynx Oesophagus Lung Stomach Pancreas Gallbladder Liver Colon and Rectum Breast Ovary Endometrium Cervix Prostate Kidney Bladder Skin Other Cancers
Systematic reviews y Analysis
Mechanisms s 1. Site-specific - part of SLR 2. General - review papers 3. Mechanisms Working Group All SLR centre mechanisms experts
GRADING THE EVIDENCE 1. Convincing Basis for 2. Probable recommendations 3. Limited Evidence Suggestive 4. Limited Evidence No Conclusion 5. Substantial Effect on Risk Unlikely
The Panel emphasises the importance of not smoking and of avoiding exposure to tobacco smoke
Nutrition Research Cancer prevention vs after cancer PREVENTION Hundreds of studies Substantial evidence Cancer seen as end Modest interest in behaviour change Little commercial AFTER CANCER Only a few studies Limited evidence Cancer seen as start Keen interest in behaviour change Much commercial
Stages of cancer survivorship Pre-treatment During treatmentt t Recovering from treatment Preventing recurrence Preventing second primaries Preventing other chronic disease Living with advanced cancer
Current sources of evidence on nutritional change after cancer Extensions of observational studies Intermediate t biomarker studies Few RCTs WHEL and WINS studies RCTs of exercise to improve symptoms Early cancer effects in cancer prevention RCTs Beta-carotene carotene, Vitamin E, Selenium, Aspirin, folate
Obesity and risk of breast cancer recurrence Recurrence risk increased by 78% among obese (BMI > 30) vs normal weight (BMI<25) Obesity risk seen in various subgroups Postmenopausal Premenopausal ER positive ER negative Even with Tamoxifen use
Physical activity and breast cancer Several small RCTs in breast cancer Consistent evidence of many benefits Increased strength Decreased fatigue Fewer treatment side effects Effects on prognosis unknown
Trials of diet change and survival after breast cancer WINS Study Low fat diet (15% kcal from fats) Reduced risk of recurrence (ER negative) WHEL study WHEL study High fruit and vegetable diet (10 servings/d) No effect on recurrence
Recommendations for cancer survivors Follow cancer prevention recommendations Seek guidance from qualified provider Different stages of cancer survivorship have Different stages of cancer survivorship have different nutritional issues
SUMMARY 1. Rigorous standardised di d peer reviewed method 2. Independent review teams 3. Comprehensive skill set 4. Comprehensive inclusion of evidence 5. Separate collection of evidence from judgement 6. International expert Panel
GOING FORWARD GOING FORWARD: The Continuous Review Comprehensive database allows ongoing assessment of the evidence
Going forward: Policy report
THE SLR CD-ROM 1. With report 2. All SLRs (>30K pages), searchable electronically 3. Associated info on methodology & SLR centres 4. Info on global network
http://www.dietandcancerreport.org
Food, Nutrition, Physical Activity, and the Prevention of fcancer: a Global Perspective
WHO 2006 Nutrition Transition
Prevalence of Obesity in European Adult Males 1980-84 % Obesity < 5 % 5-9.9% 10-14.9% 15-19.9% 20-24.9% 24 25%
Prevalence of Obesity in European Adult Males 1985-89 % Obesity < 5 % 5-9.9% 10-14.9% 15-19.9% 20-24.9% 24 25%
Prevalence of Obesity in European Adult Males 1990-94 % Obesity < 5 % 5-9.9% 10-14.9% 14 15-19.9% 20-24.9% 25% Self Reported data
Prevalence of Obesity in European Adult Males 1995-99 % Obesity < 5 % 5-9.9% 10-14.9% 14 15-19.9% 20-24.9% 25% Self Reported data
Prevalence of Obesity in European Adult Males 2000-2005 % Obesity < 5 % 5-9.9% 10-14.9% 14 15-19.9% 20-24.9% 25% Self Reported data