Focus
Spotlight
January 17, 2000
What's Your Cancer Risk?
New Web Tool Assesses Personal Cancer Risk and Supplies Prevention Information
With a wealth of epidemiological and genetic data becoming available, the development of a computer to tell you how long you can expect to live is certainly a foreseeable possibility. So too is a computer that could tell you how to modify your behavior so you could live longer by a week, year, or by decades. While such a computer might sound like a techno-character from a Michael Crichton plot line, the basis for such futurism will go live on Wednesday, January 19 when the Harvard Center for Cancer Prevention (HCCP) launches a new Web-based cancer risk assessment tool called Your Cancer Risk.Unlike the imagined futuristic computer, the HCCP site does not predict an individual's total future health experience, but it does supply a questionnaire that ultimately allows visitors to assess their risk of acquiring four specific cancers: breast, colon, lung and prostate. The personalized risk assessment gauge the site develops—measuring from low to average to high—inserts a bar where it believes a visitor's risk level should be based on the answers given. The site then allows a visitor to read about lifestyle and behavior tips that would reduce their cancer risk. And when clicking on such tips, the visitor can watch the bar on the personalized gauge drop to a perhaps more favorable level.
The site's interactive gauge allows users to witness how overall cancer risk is influenced by specific behavior choices.
"Your Cancer Risk gives people some personal idea of their cancer risk. It's at least as good as other clinical assessment tools used in doctors' offices," says David Hunter, professor of epidemiology and nutrition at the Harvard School of Public Health, head of HCCP, and one of several individuals who helped create the site. "It's also very much a teaching and communications exercise. By going through the questionnaire and seeing what the risk factors are and getting some personalized advice about how to reduce risk, I think people could learn a lot about specific cancer risk factors that aren't general knowledge."
While the Web tool has been in the design and testing stages since 1998, the epidemiological data that supports its conclusions has been collected over the last two decades in now well-known Harvard-affiliated health investigations such as the Women's Health, Nurses' Health, Physicians' Health, and Health Professionals' Studies, as well as from other non-affiliated research.
Yet, rather than undertaking the task of a formal meta-analysis of the total range of cancer research to obtain data to support the Web tool, HCCP convened a body of cancer experts from across HSPH and Harvard Medical School to winnow out a pool of risk factors covering a range of common and sometimes avoidable cancers. The cancer panels also assigned weight values to these risk factors, and created a series of behavior modification tips to reduce these values and improve an individual's risk.
The algorithm that sifts through the weighted risk factors and personal information entered by visitors will be published in Cancer Causes and Control, an HCCP peer reviewed journal. The algorithm was validated using information from the Health Professionals' Study, an HSPH-located study of 56,000 men. After creating a colon cancer risk index from the Health Professionals' Study, the HCCP team tested the index against their Web tool.
Dana Jessup and David Hunter make final preparations for the launch of the HCCP cancer assessment and prevention website, Your Cancer Risk.
The test proved the reliability of the algorithm, revealing a strong parallel between the real health of the study's participants and the colon cancer risk predicted by the algorithm.
At present, the site lists four types of cancer—estimated to represent 50 percent of the total U.S. cancer burdenÐbut updated versions of the site will include eight additional cancers: ovarian, cervical, uterine, bladder, kidney, stomach, pancreatic, and melanoma.
The site is also somewhat limited by age: it can only offer true risk assessments for those 40 and older. This age restraint exists primarily because cancers found in younger age groups are most likely to be due to genetic disposition, rather than long-term environmental factors, making risk assessment much more difficult. Another reason is that most cancer risk studies focus on older age groups, and their results don't necessarily translate to younger populations. But lastly, HCCP found through focus studies that this particular site was a stronger tool for people in mid-life or older, rather than younger generations. Despite the site's age gap, younger people could use the site to project their risk at age 40 with their current lifestyle information.
HCCP does envision the creation of a site for younger individuals. They also plan to update the current site with information from ongoing cancer research. And, to test how the Web tool influences behavior, a study is being launched at Harvard Vanguard.