Proton Therapy for Advanced Juvenile Nasopharyngeal Angiofibroma

Area of Science:

• Oncology
• Radiation Oncology
• Medical Physics

Background:

• Nasopharyngeal angiofibroma (JNA) is a rare, benign tumor typically affecting adolescent males.
• Advanced JNA often requires aggressive treatment due to its potential for local invasion and recurrence.
• Current treatment paradigms for advanced JNA may involve surgery and/or conventional photon radiotherapy (XRT).

Purpose of the Study:

• To report the initial clinical experience with proton radiotherapy (PRT) for advanced JNA.
• To evaluate the efficacy and safety of PRT in managing advanced JNA.
• To compare the dosimetric advantages and potential risks of PRT versus helical XRT for JNA.

Main Methods:

• Retrospective review of 10 patients with advanced JNA treated with PRT (45 Gy in 25 fractions).
• PRT was administered in definitive or postoperative settings between 2012 and 2022.
• Dosimetric comparisons and risk estimations for radiation-induced complications were performed against helical XRT plans.

Main Results:

• Proton radiotherapy (PRT) was well-tolerated, with only low-grade acute toxicities (CTCAE I-II).
• Achieved a 100% local control rate with a median follow-up of 27 months.
• Demonstrated significant tumor shrinkage, leading to complete remission in 5 patients and symptom relief.
• PRT yielded favorable dosimetry in critical brain substructures, suggesting reduced risks for neurocognitive impairment and CNS malignancies compared to XRT.

Conclusions:

• Proton radiotherapy (PRT) is an effective treatment for advanced JNA.
• PRT is associated with minimal acute morbidity.
• PRT holds potential for reduced long-term radiation-induced complications compared to XRT.