cancer and obesity: is there a prevention connection?
DESCRIPTION
Cancer and Obesity: Is there a Prevention Connection?. Yvonne Collins, MD, FACOG Gynecologic Oncologist Advocate Medical Group Obesity Awareness Symposium: 2012 [email protected]. Disclosure. I have no relevant conflicts of interest. Objectives. - PowerPoint PPT PresentationTRANSCRIPT
Cancer and Obesity: Is there a Prevention Connection?
Yvonne Collins, MD, FACOGGynecologic OncologistAdvocate Medical Group
Obesity Awareness Symposium: [email protected]
Disclosure• I have no relevant conflicts of
interest
I think this is hilarious! I NEVER HEARD
CREATION EXPLAINED THIS WAY BEFORE !!!
Objectives• Review obesity statistics• Review cancers directly associated with
obesity• Discuss mechanisms of obesity and cancer• Discuss the health outcomes related to
weight control and weight cancer• Explain obesity reduction efforts
Prevalence of Obesity• Greater than two thirds of US adults
were overweight or obese by 2000
• About 25% of Americans are obese as defined by a BMI of 30 > kg/M2 301.6 million people world wide are obese
• Significant health risks are related to obesity
2000
Obesity Trends* Among U.S. AdultsBRFSS, 1990, 2000, 2010
(*BMI 30, or about 30 lbs. overweight for 5’4” person)
2010
1990
No Data <10% 10%–14% 15%–19% 20%–24% 25%–29% ≥30%
Obesity no longer limited to the US
• 1.6 billion people world wide are at least overweight
• Almost 25% of people in the UK are overweight or obese.
• Even Asian countries are noticing and increase
• One can be obese yet malnourished
How is Obesity Assessed?• BMI• Weight
– Weight in earlier life– Adult weight gain
• Waist circumference; WHR• Skin folds• Body fat (DXA, BIA)• Intramuscular fat (CT scan)
By 2020, 75% of the US will be overweight
OECD Report, September 2010
Background
Body Fatness, and the Risk of Cancer
AICR/WCRF 2007
Background
Fair AM, Montgomery K. Methods Mol Biol. 2009;472:57-88.
Impact Factors
Candidate Mechanisms• Insulin and insulin like growth
factor axis• Sex steroids• Adipokines• Obesity induced hypoxia• Shared genetic susceptibility• Migrating adipose stromal cells
High Insulin Levels are an adverse prognostic factor
associated with:• Breast cancer• Colon cancer• Prostate cancer
Sex Hormones• Higher rates of conversion of
androgenic precursors to estradiol• Increased aromatase activity
through adipose tissue• Data indicates that estrogen is
both mitogenic and mutagenic
Endogenous Hormones and Breast Cancer
Collaborative Group (EHBCCG)• Nine prospective studies
• Risk of breast cancer increases at least two fold with increased levels of sex steroids– DHEA– DHEAS– Androstendione– Estrone– Estradiol– Testsosterone
Estrogen stimulation in endometrial cancer
• Increases cellular proliferation• Inhibits apoptosis• Induces synthesis of IGF-1• Progesterone induces synthesis of
IGFBP-I which inhibits IGF-I
Effect of obesity on hormones
Obesity, Hormones and Endometrial Cancer
Leptin• Leptin deficient mice overfeed and
rapidly become hyperinsulinemic• Long arm of leptin receptor (LRb)
activates– PI3 kinase– MAPK– STAT (signal transduce and activator
transcription)– C-fos
Adiponectin• Most abundant adipokine• Important insulin sensitizing agent• Inverse association of adiponecitn
concentrations and cancer• Antiproliferative effects
– ERK– ERK1– MAPK kinases– Induces p53 and Bax
Obesity Related Hypoxia
• Adipose tissue hypoxia is a key factor in the development of insulin resistance
• Regulation of chronic inflammation• Reduced adiponectin• Increased leptin• High levels of tumor hypoxia correlate
with high mortality• HIF-1 alpha is associated with poor
prognosis
Obesity related hypoxia• White adipose tissue in obese mice
is more hypoxic than in lean mice (15.2 mmHg versus 47.9 mmHg– Ye et al Am J Phys. Endo Met 2007
• Low oxygen concentrations have been associated with stimulation of melanocytes and development of melanoma – Through the AKT, ras/raf, PI-3-Kinase
pathways– Bedogni Cancer Cell 2005
Shared Genetic Susceptibility
• Genome wide studies show at least 15 loci associated with obesity
• Cancer genome maps are derived from a number of parallel genome wide associated regions
• Overlap may exist for breast on 11p and 16q– Hofker et al Nat Genetic 2009
Obesity related inflammatory markers
• Increased C-reactive protein• Activation of c-Jun NH2-terminal kinase• Activation of IkB kinase beta increases
with adiposity• Increased activated macrophage
infiltration– Now recognized as a mechanism of
insulin resistance
Mechanical Markers• Hypertension• Acid reflux• Increased iodine uptake
Breast Cancer
• Increased postmenopausal breast cancer• Decreased premenopausal cancer• Increased weight gain 18-50 increases risk
of breast cancer after menopause
Colon Cancer
• For men, increased BMI = increased risk• The strongest association with abdominal
obesity (waist circumference)• Also, increased BMI is associated with
rectal cancer
Esophageal Cancer
• Esophageal adenocarcinoma is 2X’s higher in those who are overweight and obese
• Associated link with gastroesophageal reflux and Barrett’s esophagus
• Obesity exacerbates esophageal inflammation
Prostate Cancer
• Pooled data: obesity is associated with a slight increased risk
• Obese men have more aggressive cancers• Linked to hormone and growth factors (esp
IGF-1
Other Cancers
• Obesity is associated with renal cell cancer– Related to high insulin levels
• Associated with thyroid cancer– Mechanism is unknown
• Associated with gallbladder cancer– Possible mechanism related to frequency of
gallstones
So what do we know thus farrelated to GYN cancers?
• Obesity is NOT clearly associated with:–Vaginal cancer–Vulvar cancer
• Obesity is possibly associated with:–Cervical Cancer–Ovarian cancer -
premenopausal
Obesity and Adult Weight Gain
• Strongly associated with endometrial cancer
Endometrial Cancer• Most common gynecologic cancer• We perceive it to be associated
with obesity• Increasing incidence• Hormone related cancer
Obesity• Strongest risk factor for endometrial cancer1
– RR 4.0 - BMI>32 kg/m2
– RR 6.0 - BMI>35 kg/m2
• Elevated endogenous estrogens • “Hyper-estrogenic” state does not account for
all cases2
• Other obesity-related factors may contribute to increased risk for endometrial cancer
1Brinton et al. Am J Obstet Gynecol 19922Potishman et al. JNCI 1996
Progression of the Endometrium to Cancer
• 23% of complex atypical hyperplasia (CAH) progresses to endometrial cancer
• Excess of estrogen and lack of progesterone causes abnormal proliferative drive
• Subset of aggressive histologies that do not follow this progression pathway
Normal Complex atypical hyperplasia (CAH)
Grade 1 Endometrial cancer
Endometrial Cancer: Annual Incidence and Mortality
Year Cases Deaths
1987 35,000 2,900
2008 40,100 7,170*
ACS Estimates
*250% increaseAmerican Cancer Society 2008
Goal: Prevention of deaths
40,000+ cases 7,000+ deaths34,000 endometrioid 3,71028,800 G1-2 1,820 5,200 G 3 1,890
4,000 UPSC 2,8001,200 Clear Cell 560 800 Sarcoma/CarcinoSarc 400
How do we identify these patients and prevent death?
Background
HealthyEndometrium
Complex Atypical Hyperplasia
&Endometrial
Adenocarcinoma
Estrogen Insulin Adipokines
OBESITY
DietExercise
Hormone therapyChemoprevention
Prevention of Obesity-associated Endometrial
cancer• Oral contraceptives• Progestins (including IUD w/Progestin)• Weight loss• Bariatric surgery• ? Metformin
ImplicationsEmployment/ Support system/ Cancer therapies
↓ Hormones and activity
↓ Muscle Mass
↓ Metabolic Rate ↓
Energy Needs
Weight Gain, Reduced physical
functionCo-morbidity
Changing hormonal environment
Fatigue Intake
Caffeine, sugar
PoorSleep
ReducedQOL
IncreasedMortality
LifestyleInterventionsdiet, physical
activity, weight, sleep,
etc. Reversal or
Primary prevention
Improved QOLWeight control
Implications: Obesity- related Co-morbidity
• Cardiovascular• Neurologic• Psychiatric• Pulmonary• Vascular
• Gastrointestinal• Genitourinary• Metabolic• Musculoskeletal
Modesitt, Obstet Gyn Survey, 2005
Taking care of patients can beextremely challenging…
Opportunities• Prevention of weight gain during
adolescence and early adulthood– Weight trajectory “mapping”
• Monitor for central adiposity– Waist circumference
• Monitor for risk of obesity-related disease– Metabolic syndrome
• Intervene early if weight increases• Do not under-estimate the role of
regular, moderate physical activity
Therapy: Don’t wait, Don’t hesitate
• Cancer diagnosis is an opportunity for behavior change
• Support systems are active
• Consequences (risk vs benefit) are high
• Engage healthcare team• Small changes can
translate to significant improvements in health indices and greater health and well-being
Questions?
GOG-225 Can Diet and Physical Activity
Modulate Ovarian Cancer Progression Free Survival?
Schema-GOG-225
Ovarian Cancer Diagnosis: Successful first line treatment consolidation
Comparison Lifestyle
Intervention Lifestyle: 7 servings of
vegetables and fruit , low fat (< 20%)
+ 4000 additional steps daily (weight control)
1:1intervention: comparison
Progression-free survival (@ 2 years)
RANDOMIZE
Primary Objective
• Determine if disease-free women who completed therapy for Stage II-IV ovarian, fallopian tube or primary peritoneal cancer randomized to a healthy lifestyle intervention have increased progression free survival compared to those randomized to usual care
• Opportunity to evaluate pre-randomization body mass index as a modifier of lifestyle intervention efficacy
Status
• Protocol approved• Sites processing Human Subjects
approvals• Recruitment / active enrollment • Estimate 20 new enrollees
monthly
Summary• BMI associated with cancers• Obesity is a complex system –no
on size fits all• Bariatrics (less obesity related
cancers)• Prevention methods include
– Exercise– Weight loss– Diet control
Opportunities• Cancer prevention• Much needed research
– MD Anderson endometrial SPORE• TREC (Transdisciplinary Reseach on
Energetics and Cancer)– Washington University– University California San Diego– Harvard University– University of Pennsylvania– University of Washington
References
THANKS!!!!