The effectiveness and safety of proton radiation therapy for indications of the eye : a systematic review

BACKGROUND AND PURPOSE: : Proton radiation has been used for the treatment ofuveal melanoma since 1975, but few studies have been conducted to assess itsefficacy and safety. This paper aims to systematically review the effects andside effects of proton therapy for any indication of the eye.MATERIAL AND METHODS: : A range of databases were searched from inception to2007. All studies that included at least ten patients and that assessed theefficacy or safety of proton therapy for any indication of the eye were included.RESULTS: : The search generated 2,385 references, of which 37 met the inclusioncriteria. Five controlled trials, two comparative studies and 30 case series werefound, most often reporting on uveal melanoma, choroidal melanoma and age-relatedmacular degeneration (AMD). Methodological quality of these studies was poor.Studies were characterized by large differences in radiation techniques appliedwithin the studies, and by variation in patient characteristics within andbetween studies. Results for uveal melanoma and choroidal melanoma suggestfavorable survival, with, however, significant rates of side effects. Results forchoroidal hemangioma and AMD did not reveal beneficial effects from protonradiation.CONCLUSION: : There is limited evidence on the effectiveness and safety of protonradiation due to the lack of well-designed and well-reported studies. There is a need to lift evidence on proton therapy to a higher level by performingdose-finding randomized controlled trials (RCTs), comparative studies of protonradiation versus standard given alternatives and prospective case studiesenrolling only patients treated with up-to-date techniques, allowingextrapolation of results to similar patient groups.