IgE deficiency and prior diagnosis of malignancy: Results of the 2005-2006 National Health and Nutrition Examination Survey.

BACKGROUND: Data on patients from tertiary-level health care facilities suggest that IgE-deficient (IgE <2.5 kU/L) patients have high rates of prior malignant tumors.

OBJECTIVE: To investigate the association between IgE levels and diagnosis of malignancy in non-institution-associated patients using the 2005-2006 US National Health and Nutrition Examination Survey (NHANES) cohort.

METHODS: All individuals with available IgE levels and known prior diagnosis of malignancy were divided into 4 groups: IgE deficient (IgE, <2.5 kU/L), normal IgE levels (2.5-100 kU/L), high IgE levels (100-1,000 kU/L), and very high IgE levels (≥1,000 kU/L). Rates of malignancy were compared among groups.

RESULTS: Of 4,488 individuals with data on IgE levels and malignancy status, 7.4% had a prior diagnosis of cancer. The rate of prior malignancy was significantly higher in the IgE-deficient group (12.6%) compared with individuals with high (6.7%, P = .04) and very high IgE levels (5.3%, P = 0.04). In the IgE-deficient group, only 3 patients had a diagnosis of malignancy within 3 years of IgE measurement. A mean (SD) of 10.3 (9.6) years elapsed between the time of malignancy diagnosis and IgE collection time; therefore, active neoplasm or recent chemotherapy was less likely to explain the very low IgE levels. Types of malignancies in the IgE-deficiency group included breast cancer (n = 6), nonmelanoma or unknown skin cancer (n = 3), uterine cancer (n = 2), cervical cancer (n = 1), lung cancer (n = 1), prostate cancer (n = 1), and hematologic cancer (n = 1).

CONCLUSION: In this non-institution-based cohort, IgE deficiency was associated with a higher rate of prior diagnosis of malignancies compared with individuals with high or very high IgE levels. Prospective studies are essential to better evaluate the association between IgE levels and risk of cancer.