Allergic conditions that result from hyper reactive immune system may lower cancer risk: Study

If you have asthma or eczema, your hyper reactive immune system may lower your risk of some of the most common types of cancer, according to a study published in the May 2010 issue of Annals of Allergy, Asthma & Immunology, the scientific journal of the American College of Allergy, Asthma and Immunology (ACAAI).

"Allergic conditions such as asthma and eczema that result from a hyper reactive immune system might enhance the body's ability to remove malignant cells, which might in turn lower cancer risk," said Mariam El-Zein, PhD, INRS-Institut Armand-Frappier, Laval, Québec, Canada, lead author of the article. "In our study, men with asthma had lower odds of getting stomach cancer and those with eczema had lower odds of developing lung cancer, when compared to men who did not have these conditions."

The population-based case-control study was conducted in Montreal, Québec over a seven year period among 3,300 male cancer patients and a control group of 500. Odds ratios were calculated for the association between asthma or eczema and more than 20 cancer types combined, as well as for each of eight common cancer types (stomach, colon, rectum, lung, prostate, bladder, skin and lymph nodes).

"We cannot fully explain why allergic conditions can decrease cancer risk but this research is promising," said allergist Jonathan Bernstein, MD, Fellow of the American College of Allergy, Asthma and Immunology. "We hope future studies continue to explore this connection and the role the immune system plays in reducing cancer risk."