Abstract
Purpose: :
To evaluate the clinical presentation, tumor characteristics and response to palladium-103 plaque radiation therapy for subfoveal choroidal melanomas.
Methods: :
A retrospective case series of fifty patients diagnosed with subfoveal melanoma and treated with plaque brachytherapy was performed. Patients were evaluated for tumor characteristics, visual acuity, radiation oculopathy, local tumor control and metastatic disease.
Results: :
According to the AJCC-UICC Classification System there were 26 (52%) T1 tumors, 17 (34%) T2 tumors, 5 (10%) T3 tumors, and 2 (4%) T4 tumors. Tumors were treated to a mean apical radiation dose of 82.8 Gy (over 5-7 consecutive days), resulting in a mean 157.7 Gy to the fovea. Median follow-up time was 54 months (±49.3). Forty-nine (98%) tumors were dome-shaped. Subretinal fluid (overlying or a dependent exudative retinal detachment) was present in 34 (75.6%). Pre-treatment median visual acuity was 20/50, and declined to 20/180 at the last follow-up visit. Visual acuity was better than 20/200 in 33 (66%) patients at baseline and in 25 (50%) patients at last follow up; thirteen patients (26%) lost 6 or more lines of vision. Twenty-eight patients (56%) developed radiation retinopathy with a mean time to onset of 40.6 months. Secondary intervention for radiation retinopathy was required in sixteen patients (32%) and included intravitreal anti-vascular endothelial growth factor therapy alone (n=11) or in combinations with laser (n=5), cryotherapy (n=1), or pars plana vitrectomy (n=1). The local tumor control rate of subfoveal tumors was 92%. Four patients (8%) required secondary enucleation. Metastasis developed in 2 patients (4%).
Conclusions: :
Subfoveal choroidal melanomas in this series were almost exclusively dome-shaped and likely to have an associated exudative retinal detachment. They were amenable to plaque radiation therapy. However, this tumor location was associated with a high incidence of radiation maculopathy and low incidence of radiation cataract.
Keywords: melanoma • radiation therapy • macula/fovea