Monday, October 22, 2007
My mother is one of twenty women in her neighborhood who have been diagnosed with breast cancer. And when I mean neighborhood, I'm talking about a two block radius. The women who lived next door, the lady up the street her friend in the corner house were all were affected by the same illness. Some have been fortunate and survived, like my mom. Others have passed away. But the question remains; how is it possible that so many women can come down with the same condition in such a small area? County and state public health officials investigated. Environmentalists came out to their homes... even the National Institutes of Health sent a crew to survey the area. Why breast cancer and why so many? They've never come up with a theory.
The CDC defines a cancer cluster as "a greater than expected number of cancer cases that occurs within a group of people, in a geographic area, or over a period of time. A person may suspect that a cancer cluster exists when several loved ones, neighbors, or coworkers are diagnosed with cancer." But the agency warns that many times what appears to be a "cluster" may actually reflect the normal number of cancer cases expected in a particular area. That's because cancer is a common disease. I would imagine that everyone knows at least one person who has been diagnosed with some form of the illness. Also, the term cancer can refer to a lot of different forms of the disease; a cluster usually refers to one form of cancer. And a cancer cluster may be due to chance alone. The CDC finds most cancer clusters are likely to consist of one type of cancer, a rare type of cancer or a form of cancer that is not usually found in a particular age group.
So in my mom's case, there were twenty women of different ages, different races, and different family backgrounds all with breast cancer in a tiny stretch of land. Sounds like a cluster to me.
A lot of health experts say cancer clusters are caused by the environment. For example, according to the National Cancer Institute, one in seven women living in parts of Long Island have a chance of developing breast cancer in her lifetime. New York State 2000 Cancer Registry data indicates that 500 women living in Nassau and Suffolk counties will be diagnosed this year alone. Geographic variation in breast cancer rates has been well documented, and researchers and the public are increasingly turning to environmental exposures to our air, water, soil and food to look for explanations for these pockets or clusters.
In many cases, if health officials look hard enough they can sometimes find the cause of the cancers. In Tom's River, New Jersey, 103 children were part of the nation's largest cancer cluster. State workers eventually found that 4,500 drums of toxic liquid were dumped at a nearby landfill. Federal investigators discovered in the famous "Love Canal" cancer cluster in Niagara that thousands of toxic chemicals were buried on the site 20 years before homes were built.
As I mentioned, in my mother's case, they never found the source of the problem. Officials did discover her housing development was built on an old turkey farm. Perhaps pesticides and chemicals were used on the birds, eventually permeated into the soil her home is now built on. It's difficult to say. But the problem exists.
If you think you might be a part of a cancer cluster contact your local or state health department or state cancer registry (See links here and here). These agencies provide the first level of response and have the most current local data.
Have you or someone you know been part of a cancer cluster? What did they find? Let us know.
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