Predictive significance of tissue eosinophilia for nasal polyp recurrence in the Chinese population

Background: Chronic rhinosinusitis with nasal polyps (CRSwNP) remains a challenging clinical entity with its propensity for recurrence. Tissue eosinophilia is a hallmark of CRSwNP, and its role in polyp recurrence is a subject of much investigation. Objective: The aim of this study was to evaluate the association between clinical parameters, especially tissue eosinophilia and polyp recurrence, and to identify the optimal cutoff value of tissue eosinophilia as a predictor for polyp recurrence in Chinese subjects. Methods: Overall, 387 patients with CRSwNP were enrolled in this retrospective analysis and postoperative follow-up for polyp recurrence was over a period that lasted > 24 months (mean [standard deviation], 34.03 +/- 4.95 months). The baseline demographic and clinical features and the preoperative computed tomography were compared, and mucosal specimens obtained at endoscopic sinus surgery were assessed for inflammatory cells by using histocytologic staining. Predictive factors associated with polyp recurrence were analyzed by logistic regression analysis, and optimal cutoff points of the predictors were determined by receiver operating characteristic curves and the Youden index. Results: A total of 55.3% patients (214/387) experienced recurrence. Tissue eosinophilia markedly outweighed other parameters and correlated with polyp recurrence. Receiver operating characteristic curves indicated that a cutoff value of 27% tissue eosinophils predicted recurrence with 96.7% sensitivity and 92.5% specificity (area under the curve = 0.969; p < 0.001); and an absolute count of 55 eosinophils per high power field predicted recurrence with 87.4% sensitivity and 97.1% specificity (area under the curve = 0.969; p < 0.001). Conclusion: A tissue eosinophil proportion of > 27% of total cells or a tissue eosinophil absolute count of > 55 eosinophils per high power field may act as a reliable prognostic indicator for nasal polyp recurrence within 2 years after surgery.