The results of a retrospective study of 22 patients with inverted papillomas resected by the endoscopic approach are presented with a follow-up of 33 to 96 months. Twenty-one patients had unilateral disease and one patient had bilateral involvement. None of the patients had orbital or cranial extension. One patient had synchronous carcinoma in situ. Eight patients had undergone previous surgical procedures. Following endoscopic surgery, six patients had residual disease requiring further revisions. Three of these six patients eventually required excision via limited external approaches. No patient required lateral rhinotomy or mid-facial degloving procedures. No complication occurredin any of the patients. The advantages of endoscopic surgery include precise determination of tumour extent, preservation of normal mucosa and bony structures and avoidance of external scars. Close endoscopic follow-up is mandatory to ensure early recognition and treatment of recurrent disease. Although the endoscopic approach is gaining popularity for the treatment of inverted papilloma, indiscriminate application may result in a high recurrence rate. The endoscopic approach should be performed by experienced surgeons and restricted to carefully selected patients with nasal, ethmoidal and limited maxillary disease. More extensive disease should be managed by radical external approaches or by combining endoscopic with limited external approaches.

HPV prevalence of our IP is low. EBV is not present in IP. High p21 and low p53 expression in IP suggests a non-p53-dependent regulation pathway.

Thirty-two percent of our patients had recurrence after their primary resection. Recurrences in the nasoethmoid area are usually small and resectable endoscopically under local anesthesia in the outpatient department whereas those inside the maxillary and frontal sinuses are likely to require additional external approaches under general anesthesia. A minimum of 2 years of follow-up is recommended for the preliminary report on the treatment results of this condition. Lifelong follow-up is recommended for possible late recurrences and metachronous multifocal disease.