Relationship between low serum immunoglobulin E levels and malignancies in 9/11 World Trade Center responders

Individuals with very low immunoglobulin E-(IgE)-levels have a high risk of developing malignancy. Previous studies have shown that World Trade Center (WTC)-responders exposed to carcinogens have an elevated risk of some cancers.To evaluate the association between low-serum IgE levels and cancer development in WTC-exposed-responders.IgE-levels were measured in 1,851 WTC-responders after 9/11/2001. This is the first pilot study in humans comparing the odds of developing cancer in this high-risk population, between the "low-IgE" (IgE in the lowest 3 rd percentile) versus "non-low IgE" participants.A significantly higher proportion of hematologic malignancies was found in low-IgE (4/55, 7.3%) compared with non-low IgE (26/1,796, 1.5%, p<0.01) responders. The proportion of solid tumors were similar in both groups (5.5% vs 11.4%, p>0.05). After adjustment for relevant confounders (race, sex, age at blood draw, WTC-arrival time, smoking status), the low-IgE-participants had 7.81 times greater odds (95% CI=1.77-29.35) of developing hematologic cancer when compared with non-low-IgE-participants. The hematologic cancers found in this cohort were leukemia (n=1), multiple myeloma (n=1) and lymphoma (n=2). No statistical significance was found when estimating the odds-ratio for solid tumors in relation to IgE levels.WTC-responders with low serum IgE levels had the highest odds of developing hematologic malignancies. This hypothesis-generating study suggests that low serum IgE levels might be associated with the development of specific malignancies in at-risk individuals exposed to carcinogens. Larger, multicenter studies with adequate follow up of individuals with different IgE levels are needed to better evaluate this relationship.