This series was undertaken to investigate the incidence of associated polyps and the recurrence rates of inverted papillomas with, or without, malignancies, as well as the treatment outcomes of the recurred cases.

A retrospective study evaluating the pathology, associated polyps, types of operation, recurrence rate after original operation, and surgical outcomes of recurred cases was conducted upon 96 patients diagnosed with inverted papilloma.

The overall malignancy rate was 11.5 per cent with synchronous tumours accounting for 9.4 per cent and metachronous for 2.1 per cent. Inflammatory polyps were found in association with inverted papilloma in 21.9 per cent. In cases without malignancies, the recurrence rate after the original conservative procedure was 33.9 per cent, compared to 14.3 per cent after a medial maxillectomy. In cases with malignancies, the recurrence rate after the original surgical procedure was 22.2 per cent.

Our study indicates that more aggressive and bolder surgical resection of inverted papilloma should be undertaken as a primary treatment method, or as a treatment for recurrent cases to reduce the recurrence rate of inverted papilloma with, or without, malignancy.