Nasal cavity reirradiation: a challenging case for comparison between proton therapy and volumetric modulated arc therapy

[Re-irradiation of head and neck cancers: Target volumes, technical evolutions and prospects]

Malignant tumors of the head and neck have a predominantly regional recurrence pattern, with most deaths resulting from this progression. Optimization of re-radiation in recurrence setting is a major objective for these patients. Extensive research has been carried out with the PubMed search engine to find publications dealing with this topic. The first attempts to reirradiate the ORL sphere date back to the 1980s and the first to be performed by intensity modulation conformational radiotherapy (IMRT) date back to the late 1990s. Compared to 3 dimensional conformal radiotherapy, IMRT improves clinical outcomes and reduces toxicity. In IMRT series, associated or not with concomitant chemotherapy, the locoregional control obtained at 2 years was of the order of 45 to 65% and the overall survival of 15 to 60%, depending on predictive factors. Grade 3 acute toxicity occurred on the order of 10 to 30% and late-grade 3 toxicity on the order of 15 to 50%. In a selected population with low volumes tumors, stereotactic re-irradiation at a minimum dose of 35Gy obtained outcome comparable to IMRT. Re-irradiation of head and neck tumors by proton therapy is rare. The toxicity rate appears to be lower than that usually seen after photon therapy. However, we do not have a long follow-up. This technique therefore remains reserved for search protocols and represents a future perspective in these situations.

Unresectable Ameloblastoma Successfully Treated with Definitive Proton Therapy

We report the case of an 87-year-old man affected by an unresectable ameloblastoma of the right jaw that was successfully treated by definitive proton therapy up to a dose of 66 Gy in 33 fractions. Treatment was well tolerated, and there were no interruptions due to toxicity. At follow-up visits, the patient experienced complete response to treatment with no evidence of disease and complete recovery from acute side effects. In this report, we discuss the potential and possible pitfalls of proton therapy in the treatment of specific settings.