Outcomes and toxicities of definitive radiotherapy and reirradiation using 3-dimensional conformal or intensity-modulated (pencil beam) proton therapy for patients with nasal cavity and paranasal sinus malignancies

Abstract

Background: Proton therapy (PT) improves outcomes in patients with nasal cavity (NC) and paranasal sinus (PNS) cancers. Herein, the authors have reported to their knowledge the largest series to date using intensity-modulated proton therapy (IMPT) in the treatment of these patients. Methods: Between 2013 and 2018, a total of 86 consecutive patients (68 of whom were radiation-naive and 18 of whom were reirradiated) received PT to median doses of 70 grays and 67 grays relative biological effectiveness, respectively. Approximately 53% received IMPT. Results: The median follow-up was 23.4 months (range, 1.7-69.3 months) for all patients and 28.1 months (range, 2.3-69.3 months) for surviving patients. The 2-year local control (LC), distant control, disease-free survival, and overall survival rates were 83%, 84%, 74%, and 81%, respectively, for radiation-naive patients and 77%, 80%, 54%, and 66%, respectively for reirradiated patients. Among radiation-naive patients, when compared with 3-dimensional conformal proton technique, IMPT significantly improved LC (91% vs 72%; P