An overview of the association between allergy and cancer

Abstract

Numerous epidemiological studies have evaluated some aspect of the association between a history of allergy and cancer occurrence. In this article, an overview of the epidemiological evidence is presented with a discussion of a number of methodological issues important in this area of study. Literature searches were conducted using the MEDLINE database from 1966 through to August 2005 to identify articles that explored a personal history of allergic disorders as a risk factor for cancer. Although it is difficult to draw conclusions between allergy and cancer at many sites because of insufficient evidence or a lack of consistency both within and among studies completed to date, strong inverse associations have been reported for pancreatic cancer and glioma, whereas lung cancer was positively associated with asthma. Additional studies are needed to confirm these finding and to address the limitations of previous studies, including the validity and reliability of exposure measures and control for confounding. Further, large prospective studies using cancer incidence would be particularly useful, including studies using biological markers of allergic status to reduce potential misclassification and to confirm the results of previous studies based on self-report. There is also a need for further basic research to clarify a potential mechanism, should an association exist. ' 2006 Wiley-Liss, Inc.Key words: allergy; neoplasms; epidemiology; etiology Cancer is a major threat to population health and is currently the second leading cause of death in Canada and the United States. 1,2 Cancer researchers have attempted to describe a role for various biological, lifestyle, and environmental factors in cancer development, including a potentially important role for the immune system. [3][4][5] The concept of immune surveillance, first proposed almost a century ago, 6,7 suggests that the immune system is continuously searching for and destroying tumor cells as they arise. Although historically controversial, recent scientific advancements have led to renewed interest in the immune surveillance theory. 3,[7][8][9] It has been suggested that those with a history of allergy, in particular atopic disorders, may possess an enhanced capacity for immune surveillance. [10][11][12][13] Although it has been commonly assumed that the atopic immune response offers little benefit to individuals, recently, it has been argued that it may offer a valuable evolutionary advantage. 14,15 This immune response may also be related to cancer development.Numerous epidemiological studies have evaluated some aspect of the association between a history of allergy and cancer occurrence. In this article, we provide an overview of the epidemiological evidence and discuss a number of methodological issues important in this area of study. A critical assessment of the literature in this area is important to clarify previous conflicting reports and to determine future research directions. MethodsLiterature searches were conducted using the MEDLINE database fro...

Cancer risk in hospitalised asthma patients

“…Asthma medications may also play a role in this association (Friedman et al, 1998). Although a recent review reported no association with pancreatic cancer (Turner et al, 2006), a 56% excess was noted in our study and the risk was significant even after 1 year of hospital admission. An increased occurrence of squamous cell skin cancer has not been reported earlier.…”

“…Overall, a 36% excess incidence of cancer was noted among asthma patients who had been treated in hospitals. Most earlier studies reported a reverse association or no association between asthma and the overall cancer risk (Kallen et al, 1993;Turner et al, 2005Turner et al, , 2006; a Swedish study from the earlier days of the Hospital Discharge Register reported a decreased mortality of 66% (Kallen et al, 1993). According to a recent review on cancer risk in asthma (Turner et al, 2006), only one Finnish cohort study has shown a positive association (Vesterinen et al, 1993), but significant only for men.…”

“…Most earlier studies reported a reverse association or no association between asthma and the overall cancer risk (Kallen et al, 1993;Turner et al, 2005Turner et al, , 2006; a Swedish study from the earlier days of the Hospital Discharge Register reported a decreased mortality of 66% (Kallen et al, 1993). According to a recent review on cancer risk in asthma (Turner et al, 2006), only one Finnish cohort study has shown a positive association (Vesterinen et al, 1993), but significant only for men. The number of cancer cases in our study was almost the sum of cases in three earlier cohort studies (Kallen et al, 1993;Vesterinen et al, 1993;Turner et al, 2005).…”

Allergies are associated with reduced pancreas cancer risk: A population‐based case–control study in Ontario, Canada

“…onset and diagnosis, and duration and severity of exposures, with validation of self-reported data (e.g., skin-prick testing of IgE antibodies, radioallergosorbent testing (RAST) 35 ), in order to understand the specific biological mechanisms involved in pancreas cancer development. Future epidemiological studies should also examine possible confounding due to allergy medications, as a recent study demonstrated the association between cromolyn, an antiallergy drug, and reduced pancreas tumor growth in mice.…”

Associations between Atopic Dermatitis and Risk of Gastric Cancer: A Nationwide Population-based Study

“…[28][29][30] Conversely, chronic inflammation increases the susceptibility of the affected organs to cancer, which may explain higher risks of lung cancer among patients with asthma and nasal cavity cancer among patients with allergic rhinitis. 8,17,31 Another explanation for the association between allergic disease and gastric cancer could be the inverse relationship between allergic disease and H. pylori infection, which is the most important risk factor for gastric cancer. 32 The results from this study should be interpreted in the context of the study's limitations.…”