Systematic review of effectiveness of different treatments for childhood retinoblastoma.

OBJECTIVES: To assess the clinical effectiveness of treatments for childhood retinoblastoma. DATA SOURCES: Electronic databases were searched from inception to April 2004. REVIEW
METHODS: Studies of participants diagnosed with childhood retinoblastoma, any interventions and all clinical outcomes were eligible for inclusion. Randomised and non-randomised controlled trials and cohort studies with clear comparisons between treatment groups were included. Methodological quality was assessed. A narrative synthesis was conducted. Where possible, studies assessing common interventions were grouped together, with prospective and retrospective studies grouped separately. Emphasis was placed on prospective studies.
RESULTS: Thirty-one individual studies, from 42 publications, were included in the review. Apart from one non-randomised controlled trial, only comparative studies of observational design were available for any of the treatments. Four of the included studies were prospective and the remaining 27 were retrospective. Most of the studies were of radiotherapy or chemotherapy, with few studies available on enucleation or focal treatments such as brachytherapy, photocoagulation, cryotherapy and thermotherapy. The methodological quality was generally poor, with a high risk of bias in all included studies. The main problems were in relation to how treatment was allocated and lack of consideration of potentially confounding factors, such as initial disease severity, in the study design and data analysis. The evidence base for effectiveness of treatments for childhood retinoblastoma is extremely limited. Owing to the considerable limitations of the evidence identified, it was not possible to make meaningful and robust conclusions about the relative effectiveness of different treatment approaches for childhood retinoblastoma.
CONCLUSIONS: In the authors' opinion, the evidence base for the effectiveness of treatments for childhood retinoblastoma is not sufficiently robust to provide clear guidance for clinical practice. Ideally, good-quality randomised controlled trials (RCTs) assessing the effectiveness of different treatment options for childhood retinoblastoma are required. Research is required on all the treatments currently used for this condition. Where RCTs are not feasible, for ethical or practical reasons, only high-quality, prospective, non-randomised studies should be given consideration, owing to the generally higher risk of bias in retrospective studies. To reduce the risk of confounding due to allocation by clinical indication, studies should compare patients with similar disease severity rather than compare patients of mixed disease severities. Standardised outcomes should be agreed for use in studies assessing the effectiveness of treatment. These outcomes should encompass potential important adverse effects of treatment such as loss of visual acuity and cosmetic outcome, as well as beneficial effects.