[Malignancies arising in sinonasal inverted papillomas].

Area of Science:

• Otolaryngology
• Head and Neck Surgery
• Oncology

Background:

• Sinonasal inverted papillomas are benign neoplasms of the nasal cavity and paranasal sinuses.
• These tumors are locally aggressive, prone to recurrence, and associated with malignancy, prompting research into their etiology and malignant potential.
• The exact relationship between inverted papillomas and associated carcinomas, including their origin (metachronous or synchronous), remains unclear.

Purpose of the Study:

• To investigate the incidence and characteristics of malignancy associated with sinonasal inverted papillomas.
• To compare outcomes between patients with inverted papillomas and associated squamous cell carcinomas versus those with benign inverted papillomas.
• To analyze findings in the context of existing international literature.

Main Methods:

• Retrospective review of 93 patients with sinonasal inverted papillomas treated between 1990 and 2007.
• Comparative analysis between patients with and without associated squamous cell carcinoma.
• Critical evaluation of results against global medical literature.

Main Results:

• Malignancy was found in 11.8% of patients.
• Most carcinomas (9/10) were synchronous, with only one metachronous case.
• The association between inverted papilloma and carcinoma appears indirect, with infrequent direct progression.
• Male gender, advanced age, and recurrent inverted papilloma are not definitive risk factors for malignancy.

Conclusions:

• Approximately 10% of sinonasal inverted papilloma patients develop carcinoma, with metachronous cases potentially overestimated.
• Mandatory regular follow-up is crucial after surgical resection of inverted papillomas.
• Defining high-risk groups or assuming reduced aggressiveness of carcinomas within inverted papillomas is considered hazardous.