Particle therapy for mucosal melanoma of the head and neck

Abstract

To retrospectively analyze treatment outcomes after particle therapy using protons or carbon ions for mucosal melanoma of the head and neck (HNMM) at the Hyogo Ion Beam Medical Center, as well as to compare proton therapy (PT) and carbon ion therapy (CIT). Data from 62HNMM patients without metastasis, treated with PT or CIT between October2003 and April2011 were analyzed. Median patient age was 70.5years (range 33-89years). Of the total patients, 33(53 %) had received PT and 29(47 %) had undergone CIT. Protocols for 65or 70.2GyE in 26fractions were used for both ion types. Median follow-up was 18.0months (range 5.2-82.7months). The 1-/2-year overall survival (OS) and local control (LC) rates were 93 %/61 % and 93 %/78 % for all patients, 91 %/44 % and 92 %/71 % for the PT patients and 96 %/62 % and 95 %/59 % for the CIT patients, respectively. No significant differences were observed between PT and CIT. Local recurrence was observed in 8patients (PT: 5, CIT: 3) and 29(PT: 18, CIT: 11) experienced distant metastases. Acute reactions were acceptable and all patients completed the planned radiotherapy. Regarding late toxicity, grade3 or greater events were observed in 5patients (PT: 3, CIT: 2), but no significant difference was observed between PT and CIT. Our single-institution retrospective analysis demonstrated that particle therapy for HNMM achieved good LC, but OS was unsatisfactory. There were no significant differences between PT and CIT in terms of either efficacy or toxicity.