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WHEN BRIAN HENDERSON, USC professor of preventive medicine, first arrived at the School of Medicine in 1969, he had one eye on the past and the other on a vision of the future.
In his immediate past, Henderson had studied the spread of yellow fever in Africa. The future held a different challenge: how to set up an epidemiology program to track and study a wholly different kind of
disease – cancer – in urban Los Angeles.
Henderson set about the project with the same approach he had used in his studies of infectious disease – an approach that seemed novel at the time.
“First you find out who gets the disease within a certain population. When you identify a pattern of who gets it, then you have a clue about why people are getting it,” he says.
HENDERSON, WITH PREVENTIVE medicine faculty Thomas Mack, Malcolm Pike, Susan Preston-Martin and John Hisserich, formally established the Los Angeles Cancer Surveillance Program at USC in 1972. Over the past 25 years, it has evolved from a voluntary agreement with hospital, clinic and laboratory pathologists to send USC researchers notice of all diagnosed cancer cases in the area to an official depository of cancer information for regional, state and national cancer registries.
The CSP computerized database now exceeds 1 million records, with more than 37,000 newly diagnosed cancer cases added each year.
CSP has also provided epidemiologists with a unique research resource. Scientists can use the records to identify and contact eligible cancer patients soon after diagnosis. Over the years, some 25,000 cancer patients have taken part in CSP studies.
Under the leadership of Ronald Ross, a professor of preventive medicine who oversees the cause and prevention research programs at the USC/Norris Comprehensive Cancer Center, the pace of research based on data from this cancer registry has continued to accelerate, with at least two scientific studies published each month.
“It’s clear that the USC-based registry has enabled scientists to develop a clearer understanding of cancer,” Ross says. “In particular, the CSP continues to be a leader in developing new ways to do population-based studies of disease and evaluating demographic patterns of cancer risk.”
RESEARCH WAS ALWAYS part of the program’s aim, says Henderson.
“From the beginning, we set up a system that would identify the people who were getting cancer but also allow us to follow up on why these people were getting disease.” he says. “We never meant it to be a passive archive of data. Instead, we pictured it – as it has turned out to be – an active surveillance system that scientists would use.”
Over the years, CSP has made many innovations that have improved the quality of the data it collects. Early on, epidemiologist Thomas Mack introduced a better method of identifying matched controls for cancer studies, freeing the studies from some of what epidemiologists call bias by selecting controls in a more random manner.
To this day, so-called neighborhood walkers go door-to-door to locate healthy people who have basic things in common – where they live, how old they are and what gender – with cancer patients enrolled in studies.
Only a population-based cancer registry like the CSP can give health researchers an idea about how cancer incidence changes from year to year or whether one neighbor-hood has a much higher incidence than another.
“We get calls from doctors or the lay public who say, ‘There seems to be a lot of cancer in my neighborhood,’” says CSP executive director Dennis Deapen. “Because we have a population-based approach, we can actually calculate the rate in that specific area.”
Most often, the fears are unfounded, he says.
“The cancer registry data really make it clear that most cancers don’t have to do with exactly where you live, but with influences from race and ethnicity, smoking, diet and other lifestyle and genetic factors,” he says.
For example, despite what much of the public believes, lung cancer is no more common in smoggy Los Angeles than in wind-swept San Francisco.
“The only way we know that is because of the CSP,” Deapen says. “Brian Henderson showed true foresight when he founded the program.”
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