Cancer Epidemiology: The need for Global Information sharing in obesity

and cancer?Edinburgh, August 2011

Faina Linkov, PhDResearch Assistant Professor

University of Pittsburgh

What is cancer?Cancer is a term used for diseases in

which abnormal cells divide without control and are able to invade other tissues.

Only 5–10% of all cancer cases can be attributed to genetic defects, whereas the remaining 90–95% have their roots in the environment and lifestyle.

Cancer is not just one disease but many diseases. There are more than 100 different types of cancer.

While many diseases (such as heart failure) may have a worse prognosis than most cases of cancer, it is the subject of widespread fear and taboos.

Increase in uterine cancer mortality might be associated with increase in obesity epidemic

Why is it important to prevent cancer?

• Treatment options are not available for several forms of cancer

• Existing cancer treatments do not target specific cancer cells

• Existing cancer treatments have many undesirable side effects and are not always 100% effective

• One of the main causes of failure in the treatment of cancer is the development of drug resistance by the cancer cells.

Obesity and Cancer: Mechanisms

Adipose tissue is an active endocrine organ

Mechanisms by which adipose tissue may influence cancer risk

- Production of sex steroid hormones (e.g., estrogen, androgen) - Effects on insulin sensitivity and production of insulin-like growth

factors - Actions on other hormones in adipose tissue (e.g., leptin,

adiponectin) - Increases in oxidative stress and chronic low-grade inflammation

that affect the body’s immune response

Obesity as a common phenomenon

In 2009, no state met the Healthy People 2010 obesity target of 15%, and the self-reported overall prevalence of obesity among U.S. adults had increased 1.1 percentage points from 2007.

What is media saying about obesity and cancer?

1998

2003

http://www.usatoday.com/news/health/2005-05-25-obesity_x.htm

2005

2007

2007

What is the awareness of obesity as a risk factor for

cancer?

Data from American Institute for Cancer Research (AICR)

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2009 Cancer Risk Awareness2009 Cancer Risk Awareness

How much excess weight is too much???

Obesity and Mortality from CancerNEJM April 2003

NEJM 348:1625(April 2003)

Mortality from Cancer According to BMI for U.S. Men in the

Cancer Prevention Study II

My research interests:Endometrial cancer risk reduction

in the context of weight loss through bariatric surgery

Why bariatric surgery?Traditional diet and exercise

weight loss programs do not result in sustainable weight loss. Up to 90% of dieters regain weight. Bariatric surgery potentially offers means to lose weight and keep it off

Unadjusted cumulative mortality for subjects who underwent bariatric surgery vs. controls

From Sjöström et al. August 23, 2007

Endometrial Cancer: Incidence and Prevalence

• Most common gynecologic cancer• 4th most common in women (US)• 5th most common in women (worldwide)• approximately 39,080 new cases of

endometrial cancer are diagnosed yearly in the US

• about 7400 women will die from the disease this year

• While we do not have specific markers for endometrial cancer, we know that various inflammatory markers, adipokines, and cancer antigens have been associated with the disease

What kind of studies can we propose?

It is particularly interesting to explore weight loss in relation to endometrial cancer risk because limited evidence suggests that premalignant changes in the endometrium can potentially be reversed with achieving more optimal weight.

Why is bariatric surgery patients ideal group for this research?

• Rapid weight loss within short period of time• High risk for endometrial cancer and other

malignancies• Many routine care appointments (can overlap

with research appointments)• Relatively healthy, potential for long term

follow up

Information that is being collected• Blood• Urine• Health forms (including

General Health form, reproductive health form, SF-36, CES-D, MAQ, Sleep scale)

• Endometrial biopsy (only for a pilot study supported by Scaife foundation)

1938The era of cancer treatment

2011The era of cancer prevention

Baruch Blumberg and prevention of liver cancer

(July 28, 1925 – April 5, 2011)

Discovery of hepatitis vaccine prevented large number of primary liver cancers, especially in the developed world

Cancer Supercourse Status

• Over 200 lectures• Over 500 faculty members with interest in

cancer• Translation in up to 5 languages for selected

sets of lectures

Raj Bhopal: Concepts of Epidemiology course in the Supercourse

Future directions

• The long-term goal is to investigate mechanisms by which obesity promotes endometrial cancer development and weight loss reduces the risk of endometrial cancer development.

• Targeting studies where patients lost weight through means other than bariatric surgery is one of the things that we are currently working on

• Sharing information about cancer prevention with scientists around the world using the Supercourse

At the end of our fight against cancer, there can be only one…

That one is prevention

Contact Faina Linkov at faina.linkov@gmail.com with any questions or

new ideas.