Proton therapy – A systematic review of clinical effectiveness

• Published in: Radiotherapy and oncology Vol. 83; no. 2; pp. 123 - 132
• Main Authors: Olsen, Dag Rune, Bruland, Øyvind S, Frykholm, Gunilla, Norderhaug, Inger Natvig
• Format: Journal Article
• Language: English
• Published: Ireland Elsevier Ireland Ltd 01.05.2007
• Subjects: Clinical effectiveness; Hematology, Oncology and Palliative Medicine; Humans; Neoplasms - radiotherapy; Outcome Assessment (Health Care); Proton therapy; Protons - therapeutic use; Radiotherapy Dosage; Radiotherapy, High-Energy - methods; Systematic review; Technology Assessment, Biomedical; Systematic review; Clinical effectiveness; Proton therapy
• ISSN: 0167-8140; 1879-0887
• DOI: 10.1016/j.radonc.2007.03.001

Abstract Background and purpose Proton therapy is an emerging treatment modality for cancer that may have distinct advantages over conventional radiotherapy. This relates to its ability to confine the high-dose treatment area to the tumour volume and thus minimizing radiation dose to surrounding normal tissue. Several proton facilities are currently operating or under planning world-wide – in the United States, Asia and Europe. Until now no systematic review assessing the clinical effectiveness of this treatment modality has been published. Materials and methods A systematic review of published studies that investigated clinical efficacy of proton therapy of cancer. Results We included 54 publications: 4 randomized controlled trials (RCTs) reported in 5 publications, 5 comparative studies and 44 case series. Two RCTs addressed proton irradiation as a boost following conventional radiation therapy for prostate cancer, where one demonstrated improved biochemical local control for the highest dose group without increased serious complication rates. Proton therapy has been used to treat a large number of patients with ocular tumours, but except for one low quality RCT, no proper comparison with other treatment alternatives has been undertaken. Proton therapy offers the option to deliver higher radiation doses and/or better confinement of the treatment of intracranial tumours in children and adults, but reported studies are heterogeneous in design and do not allow for strict conclusions. Conclusion The evidence on clinical efficacy of proton therapy relies to a large extent on non-controlled studies, and thus is associated with low level of evidence according to standard heath technology assessment and evidence based medicine criteria.