Squamous cell carcinoma arising in a sinonasal inverted papilloma

Sinonasal inverted papilloma (SNIP) has the capability to recur and undergo pre-malignant/malignant transformation. The estimated incidence of carcinoma associated with sinonasal papilloma varies widely, ranging from 5% to 15% across published literature. It may occur as coexistence of carcinoma and papilloma in the same lesion (synchronous), or a small focus of carcinoma developing within an inverted papilloma, and lastly, a carcinoma appears at the site of excision of a benign papilloma (metachronous). Possible factors like human papillomavirus infection (HPV), smoking, occupational exposure, and genetic abnormalities, including epidermal growth factor receptor (EGFR) mutations, have been implicated in the malignant transformation of sinonasal papillomas. We report malignant transformation in an inverted papilloma of maxilla in a 31-year-old female.