Smoking and malignancy in sinonasal inverted papilloma

Abstract

Objectives/Hypothesis The authors investigated clinical features of squamous cell carcinomas (SCC) arising in sinonasal inverted papillomas (IP) and risk factors responsible for their malignant transformation. Study Design Retrospective analysis. Methods In total, 162 patients diagnosed with sinonasal IP and treated between 1998 and 2009 at Pusan National University Hospital were enrolled. Their demographic data, information about previous surgery, smoking history, treatment modalities, follow-up duration, recurrence, and presence of malignancy were reviewed retrospectively. Results Seventeen patients (10.5%) were diagnosed with SCC arising in sinonasal IPs. Among them, nine (9/162, 5.6%; 9/17, 52.9%) were diagnosed with synchronous malignancies and three (3/162, 1.8%; 3/17, 17.6%) were diagnosed with metachronous malignancies. In five cases (5/162, 3.1%; 5/17, 29.4%), we could not determine whether their malignancies were synchronous or metachronous. Among 53 smokers, 14 (26.4%) had malignant transformation, while only three (2.8%) in 109 nonsmokers had malignant transformation (Odds ratio = 12.7; P