Metastasis rates and sites after treatment for choroidal melanoma by proton beam irradiation or by enucleation

PURPOSE: To investigate tumor thickness and location, the interval of time between treatment for choroidal melanoma (proton beam irradiation or enucleation) and diagnosis of metastatic disease, and rates and sites of metastasis. DESIGN: Retrospective, interventional, noncomparative case series. METHODS: Follow-up of 152 patients with primary choroidal melanoma, between 1992 and 2006 (14 years). One hundred and twenty-one patients were treated with proton beam irradiation and 31 patients were treated with enucleation. Baseline and annual or semiannual ophthalmic examination, B-scan ultrasonography, systemic and laboratory evaluations (liver enzymes, chest X-ray, ultrasonography or magnetic resonance imaging of the liver) were performed according to a standard protocol. RESULTS: Nineteen patients (12.5%) were diagnosed with metastasis during follow-up time after treatment for choroidal melanoma. Thirteen patients (10.7%) of the irradiation group and 6 patients (19.3%) of the enucleation group were diagnosed with metastasis. Eight patients (6.6%) of the irradiation group and 5 patients (16.1%) of the enucleation group were diagnosed with liver metastasis. Ocular complications after proton beam irradiation were recorded. Fifty-nine patients (48.7%) of the irradiation group presented with cataract. Other complications were retinal detachment, retinopathy, vitreous haemorrhage, iris neovascularization, neovascular glaucoma, optic neuropathy, and corneal opacification. CONCLUSIONS: In our series, 10.7% of the irradiation group and 19.3% of the enucleation group were diagnosed with metastasis. The liver was the most common site of metastasis in both groups. Cataract was the most common complication in the irradiation group.