Inverse Association Between Contact Allergy and Cancer?

An inverse association has been found between contact allergy and non-melanoma skin and breast cancer, and a positive association between contact allergy and bladder cancer, according to a study published online July 11 in BMJ Open.

Kaare Engkilde, PhD, from Copenhagen University Hospital Gentofte Denmark, along with colleagues examined the relationship between contact allergy and cancer. Databases had been linked between the Danish Cancer Register and a tertiary hospital patient register noting patients affected by dermatitis who had been patch tested for contact allergy. Only 40 patients were studied as part of the investigation. Final associations were examined by logistic regression analysis.Researchers found an inverse relationship between contact allergy and non-melanoma skin and breast cancer within men and women. Women with contact allergy also demonstrated an inverse trend for brain cancer. Contrary to the previous inverse correlations, bladder  cancer and contact allergy were found to be positively linked

"The inverse associations support the immunosurveillance hypothesis (i.e., individuals with an allergy are less likely to get cancer due to a triggered immune system), while the positive association with bladder cancer could be due to accumulations of chemical metabolites in the bladder," the authors write.

This study of only 40 people resulted in similar findings of a study published earlier this year in Feb. 7 Cancer Epidemiology, Biomarkers & Prevention noting an inverse connection between allergies and brain cancer. Review the AbstractRead the Full Text