Purpose: Some patients with previously treated, unresectable, recurrent or metastatic head and neck malignancies are not amenable to curative-intent treatment. Here, we investigated the quad-shot (RTOG 8502) regimen of hypofractionated proton radiotherapy (RT) in that patient population.
Materials and methods: From 2013 to 2015, 26 patients with recurrent or metastatic cancers were treated with palliative proton RT to the head and neck with quad shot (3.7 Gy twice daily for 2 days). Patient characteristics and survival data were reviewed.
Results: Seventeen (65%) patients received ≥ 3 quad-shot cycles and 23 (88%) had prior head and neck RT. Overall palliative response was 73% (n = 19). The most common presenting symptom was pain (50%; n = 13), which improved in 85% (n = 22) of all patients. The overall grade-1 acute-toxicity rate was 58% (n = 15), and no acute grade 3 to 5 toxicities were observed.
Conclusions: The proton quad-shot regimen demonstrates favorable palliative response and toxicity profile, even in patients that received prior RT.
Keywords: head and neck cancers; palliation; proton therapy; quad shot; radiotherapy.