Multifield optimization intensity modulated proton therapy for head and neck tumors: a translation to practice

Area of Science:

• Radiation Oncology
• Medical Physics
• Oncology

Background:

• Head and neck tumors present complex treatment challenges due to proximity to critical structures.
• Intensity Modulated Proton Therapy (IMPT) offers potential for precise dose delivery, minimizing toxicity.
• Multifield Optimization (MFO) is an advanced technique within IMPT aiming to further improve dose distribution.

Purpose of the Study:

• To report the first clinical experience and toxicity profile of MFO-IMPT in patients with head and neck tumors.
• To evaluate the feasibility and early clinical outcomes of this novel treatment approach.

Main Methods:

• Fifteen patients with head and neck cancer (including SCC and adenoid cystic carcinoma) received MFO-IMPT.
• Treatment involved active scanning beam proton therapy with doses of 70 Gy (chemoradiation) or 66 Gy (radiation alone).
• Plan robustness was assessed against setup uncertainties and proton range variations.

Main Results:

• All 15 patients completed MFO-IMPT without treatment breaks or hospitalizations; no treatment-related deaths occurred.
• A high overall clinical complete response rate of 93.3% was observed at a median follow-up of 28 months.
• Common toxicities included xerostomia (all patients) and mucositis (all patients), with no grade 2+ anterior oral mucositis.

Conclusions:

• This is the first clinical report detailing the use of MFO-IMPT for head and neck tumors.
• Early clinical outcomes, including a high response rate and manageable toxicity, are encouraging.
• Further investigation in prospective clinical trials is warranted to confirm the efficacy of MFO-IMPT.