Increased Hazard Risk of First Malignancy in Adults with Undetectable Serum IgE: a Retrospective Cohort Study.

Purpose: The clinical relevance of IgE-deficiency is not established. Previous studies have postulated a relationship between absent serum IgE and the incidence of specific malignancies. We sought to examine the relationship between undetectable total serum IgE (< 3 IU/mL) and first malignancy, considering both general all-cause malignancy risk and risk of specific malignancy subtypes in adult subjects. Methods: Retrospective cohort study at a single center of 39,965 adults aged 18 or older (median age 51, 65.1% female) with at least one serum total IgE measurement from 1998 to 2020. Analytics included chi² table and logistic regression modeling of the main outcome measures, which include diagnosis of first malignancy and first diagnosis of specific malignancy subtype. Results: Of the entire cohort, 2584 subjects (6.5%) developed a first malignancy and 2516 (6.3%) had an undetectable IgE. Of those with undetectable IgE levels, 8.9% developed a first malignancy versus 6.3% with detectable IgE measurements. After adjusting for risk factors, there was a significant association between undetectable IgE and risk/hazard of first malignancy (relative risk 1.49, 95% confidence interval (CI) 1.27–1.75) (hazard ratio 1.28, 95% CI 1.08–1.52). Results were similar in multiple sensitivity analyses. For type of malignancy developed, undetectable IgE was associated with increased risk of hematologic malignancy (relative risk 2.07, 95% CI 1.29–3.30) and skin malignancy (relative risk 1.52, 95% CI 1.13–2.05). Conclusion: Compared to individuals with detectable IgE levels, patients with undetectable total serum IgE had increased risk and hazard of first malignancy in general, and increased risk of hematologic malignancy in particular. [ABSTRACT FROM AUTHOR]