Assessment of Biomarker Heterogeneity in Sinus Versus Inferior Turbinate Tissue in Patients Without Chronic Rhinosinusitis.

Abstract

Currently, no consensus exists on the appropriate control specimen site to utilize in studies evaluating for biomarkers in chronic rhinosinusitis (CRS). Studies thus far have utilized tissue from various anatomic sites despite regional heterogeneity. We set out to quantify the differences in biomarker levels present in inferior turbinate versus sphenoid sinus mucosa in paired healthy control patients. We hypothesize that statistically significant differences in cytokine/chemokine expression exist between these two distinct sites. A 38-plex commercially available cytokine/chemokine Luminex Assay was performed on 54 specimens encompassing paired inferior turbinate and sphenoid sinus mucosa samples from 27 patients undergoing endoscopic anterior skull base surgery. Patients with a history of CRS were excluded. Paired sample t-tests and Fisher's exact tests were performed. Twenty-seven patients were included in the study, including 10 male and 17 female patients with an average age of 48 years. The following 8 biomarkers had statistically significant concentration differences between inferior turbinate mucosa and sphenoid mucosa sites: Flt-3L, Fractalkine, IL-12p40, IL-1Ra, IP-10, MCP-1, MIP-1β, and VEGF, with all P-values <0.01. No consensus exists regarding the optimal choice of control specimen for CRS research. We present statistically significant quantitative differences in biomarker levels between paired inferior turbinate and sphenoid mucosa samples. This confirms the presence of heterogeneity between different subsites of sinonasal mucosa and highlights the need for standardization in future CRS research.