Re: Association of immunoglobulin E levels with glioma risk and survival

We read with great interest the recent article by Guerra et al. on the association of immunoglobulin E levels with glioma risk and survival. The authors performed a case-control study, and serum IgE levels for total, respiratory, and food allergies were measured in adults diagnosed with glioma and matched individuals. The results showed that elevated total IgE was associated with reduced risk of IDH-wildtype and IDH-mutant glioma. Positive respiratory IgE was linked to better survival for IDH-wildtype glioma in multivariable Cox regression.¹

Several studies have consistently shown an inverse association between self-reported allergies and glioma.² However, it is yet unknown what mechanism underlies the association between glioma susceptibility and IgE-mediated atopic disease. In other central nervous system tumors, such as meningiomas, an inverse relationship with history of allergies and a biomarker of atopic allergy was also reported.³ In a previous study, we have investigated total IgE levels among patients with different primary and metastatic intracranial tumors. We found that primary intracranial tumors had significantly lower IgE levels than metastatic tumors.⁴ Preoperative differentiation of metastatic tumors from other intra-axial lesions such as gliomas and central nervous system lymphomas (CNSL) is of paramount importance because of differing treatment strategies. All these lesions have overlapping radiological features, and even histopathological analysis of tissue removed via surgery or stereotactic biopsy does not have 100% accuracy.⁵ Furthermore, for CNSL the role of surgery is unclear; for gliomas and metastasis the extent of resection is of prognostic significance and early recognition of a metastatic lesions is important for the further investigation to detect the primary site of cancer. Based on these, we believe that IgE levels apart from a prognostic role in gliomas might hold an additional role in differentiating between different intracranial neoplastic entities. It is obvious that future studies are definitely needed in order for safe conclusions to be reached.

Author contributions

George Alexiou, MD (Conceptualization; Methodology; Writing—original draft; Writing—review & editing), Panagiota Zagorianakou, MD (Data curation; Methodology; Writing—original draft), and Spyridon Voulgaris, MD (Conceptualization; Writing—review & editing)

Funding

None declared.

Conflicts of interest

None declared.

Data availability

No new data were generated or analyzed for this letter to the editor.