Histological characteristics of chronic rhinosinusitis with nasal polyps: Recent 10-year experience of a single center in Daegu, Korea

Chronic rhinosinusitis with nasal polyps (CRSwNP) has various histological patterns and the immunologic characteristics differ between eastern and western patients. This study assessed the histological pattern of Korean NPs and determined whether Korean NP patterns have become westernized. Three hundred forty-nine CRSwNP patients were enrolled in this study in 2001 (n = 107), 2006 (n = 111), and 2011 (n = 131). Histological type was categorized as eosinophilic, neutrophilic, seromucinous gland hyperplasia, and stromal atypia types. Medical records were reviewed for their atopic status, olfactory function, and computed tomography (CT) score. The eosinophilic type was significantly increased in 2011 (62.6%) when compared with 2001 (52.3%) and 2006 (47.7%). The incidence of atopic NPs was significantly higher in 2006 (18.9%) and 2011 (21.5%) than in 2001 (14.0%). Although atopic status and CT score were not significantly different among three NP types, anosmia was more common in eosinophilic NPs. The prevalence of NPs with atopy and eosinophilic NPs has continuously increased in Korea, indicative that the sinonasal disease pattern is becoming similar with western countries.