Radiotherapy for inverted papilloma: a case report and review of the literature

BACKGROUND: Sinonasal inverted papilloma (IP) is a rare, usually benign tumor arising from the respiratory mucosa of the sinonasal tract. Surgical resection is the treatment of choice. In histologically overt benign IPs (i.e. without associated malignancy) irradiation was employed only anecdotally. The patient with gross residual of benign IP after up-front surgery that was subsequently treated with irradiation is presented and the literature reports on the use of radiotherapy (RT) in this tumor type are reviewed. CASE REPORT: After the surgical treatment the residuum in the region of the sphenoid and adjacent cavernous sinus was irradiated to 54 Gy in 1.8 Gy daily fractions. No recurrence or deterioration of olfaction, hearing or vision was observed 2.6 years post-RT. REVIEW OF THE LITERATURE: In the literature, six reports were identified with 16 patients describing necessary details on RT and outcome. Twelve of 14 cases (our case included) with gross or subtotal tumor resection and postoperative RT were locally controlled. The lowest and the median irradiation doses were 47.15 Gy and 56.5 Gy, respectively, and the follow-up period ranged between 0.5–20.5 years (median 7.8 years). CONCLUSIONS: RT is safe and valuable treatment option in histologically overt benign IPs. It is indicated when the risk of tumor recurrence after surgery is increased and in inoperable tumors.