“…With some exceptions (8–10), the majority of studies have found that allergic conditions may reduce glioma risk by as much as 20–40% (1–4, 7). These associations have been examined using single- [i.e., (11)], multi-site [i.e., (12–14)], and nested case-control studies [i.e., (15, 16)], prospective cohort studies [i.e., (3)], and meta-analyses [i.e., (1, 2, 7)]. Additionally, the observed inverse association between allergies and glioma has remained consistent across studies with different exposure assessment strategies, such as self-reported allergy status (3), self-reported physician-diagnosed allergies (12, 13, 17–19), number of allergy types (12, 17), and allergy-related biomarkers, such as Immunoglobulin E [overall (4, 11, 16, 20), pre-diagnostic (16, 21), and/or allergen-specific (11, 15, 16)], soluble CD23 levels (22), and polymorphisms in allergy-related genes (23–26).…”