Smoking is an independent association of squamous metaplasia in Chinese nasal polyps.
BACKGROUND
Nasal polyposis demonstrates histological features of epithelial remodeling and variable inflammatory cellular infiltration. We studied a large series of Chinese nasal polyp (NP) samples to characterize these histological features and their associations with clinical characteristics.


METHODS
A detailed histological study of nasal polyposis was performed employing various histopathological techniques. A total of 153 intraoperative NP biopsies were analyzed histologically. Sections were examined under microscopy to determine the percentages of different types of inflammatory cells, and types of epithelial remodeling. Two systems of subtyping NPs based on inflammatory cell infiltration were assessed. These were correlated with patient characteristics.


RESULTS
Epithelial remodeling patterns include epithelial hyperplasia (87.8% of specimens), goblet cell hyperplasia (53.2%), and squamous metaplasia (44.6%). Smoking was a strong independent association of squamous metaplasia (adjusted odds ratio [OR] 9.9; 95% confidence interval [CI], 4.2 to 22.9; p < 0.01). The most common inflammatory cells were neutrophils (median of 12.8%) and CD8+ T cells (12.8%), followed by macrophages (11.0%), CD4+ T cells (9.7%), eosinophils (8.6%), and mast cells (7.6%). We defined 2 systems to classify NPs based on proportions of eosinophils and neutrophils. The majority of NP samples were neutrophilic. The first classification system has greater histological correlation. Based on the first classification, eosinophilic nasal polyposis was associated with epithelial hyperplasia (OR 3.7, p = 0.019) and goblet cell hyperplasia (OR 3.4, p < 0.001).


CONCLUSIONS
The majority of Chinese NPs are neutrophilic and epithelial hyperplasia is the most common pattern of epithelial remodeling. We show for the first time that smoking has a strong association with squamous metaplasia in nasal polyposis.
Department of Otolaryngology, Second Affiliated Hospital of Harbin Medical University, Heilongjiang, China.
Tian
T
Gao
Department of Otolaryngology, National University of Singapore, National University Health System, Singapore.
Chew Lip
CL
Ng
Department of Otolaryngology, National University of Singapore, National University Health System, Singapore.
Chunwei
C
Li
Department of Otolaryngology, National University of Singapore, National University Health System, Singapore.
Ying Ying
YY
Li
Department of Otolaryngology, National University of Singapore, National University Health System, Singapore.
Chen
C
Duan
Biostatistics Unit, National University of Singapore, National University Health System, Singapore.
Liang
L
Shen
Department of Pathology, Second Affiliated Hospital of Harbin Medical University, Heilongjiang, China.
Yu Fei
YF
Jiao
Department of Otolaryngology, Second Affiliated Hospital of Harbin Medical University, Heilongjiang, China.
Ming
M
Liu
Department of Otolaryngology, National University of Singapore, National University Health System, Singapore.
De Yun
de Y
Wang
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D056151:Airway Remodeling; D015415:Biomarkers / Q000378:metabolism; D002648:Child; D002675:Child, Preschool; D002681:China; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D016015:Logistic Models; D008297:Male; D008679:Metaplasia; D008875:Middle Aged; D009298:Nasal Polyps / Q000378:metabolism / Q000473:pathology*; D012907:Smoking / Q000009:adverse effects*; D055815:Young Adult
D015415:Biomarkers
Asian; Chinese; chronic sinusitis; epithelial remodeling; nasal polyposis