Efficacy and safety of proton therapy versus intensity-modulated radiation therapy in the treatment of head and neck tumors: A systematic review and meta-analysis

To comprehensively evaluate the therapeutic efficacy and safety when utilizing proton therapy (PT) versus intensity-modulated radiation therapy (IMRT) in head and neck cancer patients. Pubmed, ScienceDirect, Embase, Scopus, and Web of Science were systematically searched for studies on comparative PT and IMRT outcomes. We performed a random effect model meta-analysis to estimate the hazard ratio (HR) and odds ratio (OR) for efficacy and safety outcome variables between PT and IMRT. From 641 identified articles, 11 studies met the inclusion criteria, comprising 3087 patients (606 treated with PT and 2481 with IMRT). On toxicity analysis, PT is associated with decreased acute grade 1 nausea (OR = 0.34, 95% CI: 0.13-0.84, p = 0.02) compared to IMRT. In grade 2 toxicity, PT showed significant advantages over IMRT in mucositis (OR = 0.44, p < 0.0001), dysgeusia (OR = 0.35, p = 0.02), dysphagia (OR = 0.36, p < 0.0001), fatigue (OR = 0.29, p = 0.001), pain (OR = 0.34, p = 0.01), and weight loss (OR = 0.54, p = 0.02). Proton therapy also exhibited increased safety in grade 3 dysphagia incidence (OR = 0.44, p < 0.0001) compared to IMRT. PT demonstrated improved overall survival (OS) compared to IMRT across multiple time points: 1-year OS (HR = 0.43, p = 0.02), 2-year OS (HR = 0.44, p < 0.0001), and 5-year OS (HR = 0.78, p = 0.004). In terms of disease-free survival (DFS), PT also showed improved outcomes at 2-year DFS (HR = 0.65, p = 0.03) and 5-year DFS (HR = 0.81, p = 0.03). Proton therapy demonstrated superior overall survival (OS), disease-free survival (DFS), and better local control rate (LCR) compared to IMRT. The data also showed better safety outcomes in PT patients, particularly when involving grade 2 acute toxicity events.