Lower-neck sparing using proton therapy in patients with uninvolved neck nasopharyngeal carcinoma: is it safe?

Undifferentiated carcinoma of the nasopharynx (NPC) is a rare disease, which usually occurs in the Asian population. Due to its anatomic location, it is characterised by rich lymph node drainage and has a high incidence of cervical node metastasis. However, cervical nodal metastasis commonly involves retropharyngeal nodes and level II nodes, followed by level III nodes. In recent years, innovations in terms of systemic treatments and radiotherapy techniques have improved oncological outcome and treatment-related toxicities. Therefore, there is a growing interest in de-intensification strategies of reducing volumes and treatment-related side effects, especially in patients with NPC with N0-N1-stage disease. Proton therapy could represent a valid alternative to Intensity Modulated Radiotherapy (IMRT) in the management of NPC in this setting. With this Commentary, we aim to explore the feasibility of Intensity Modulated Proton Therapy (IMPT) in upper-neck irradiation of NPC N1-stage disease. We selected an NPC patient with N1 disease and compared the original IMRT plan with the IMPT plan in terms of dosimetric parameters. IMPT offers a minimal dosimetric advantage over IMRT in the bilateral lower-neck sparing. Clinical trials are needed to evaluate the significance of these proposed suggestions and their applicability in non-endemic areas.