Objective: Our previous study revealed that serum amyloid A (SAA) levels in polyp tissues could serve as a biomarker for the prediction of corticosteroid insensitivity in patients with chronic rhinosinusitis with nasal polyps (CRSwNP). However, their association with disease control status in the patients after endoscopic sinus surgery remains to be assessed.
Methods: Polyp tissues and control uncinate process mucosa were collected from 48 patients with CRSwNP and 10 healthy control subjects. SAA expression was examined using immunohistochemistry and enzyme-linked immunosorbent assay. Receiver operating characteristic (ROC) curves were performed to determine the predictive value of SAA in nasal polyps. The clinical characteristics of 2 CRSwNP subtypes (SAAhigh and SAAlow) were evaluated.
Results: The SAA expression levels in polyp tissues were significantly elevated both in non-eosinophilic and eosinophilic CRSwNP as compared to the healthy controls. In patients with CRSwNP, the tissue SAA level was significantly higher in the disease-controlled patients than those of the partly controlled and uncontrolled. ROC curve analysis revealed that a cut-off value of 114.9 ng/mL for the tissue SAA level predicted the patients with disease-controlled status with 93.33% sensitivity and 63.64% specificity (AUC = .8727, P < .001). Furthermore, The SAAhigh subgroup showed higher tissue eosinophil numbers and percentage of the disease-controlled patients compared to the SAAlow subgroup.
Conclusions: Our findings suggest that measurements of SAA in polyp tissues may provide useful information for evaluating CRSwNP conditions, especially identifying the CRSwNP patients with disease-controlled status after endoscopic sinus surgery.
Keywords: chronic rhinosinusitis; disease control; nasal polyps; serum amyloid A.