Melanomas’ most frequent location is the choroid, and the one with the most benign prognosis is the ciliary body. The mortality rate up to five years for ciliary body or choroidal melanoma metastasis is of approximately 30% in comparison with the 2-3% that represents the iris melanoma. They tend to be asymptomatic but they must be taken into account as part of the differential diagnostic if there is unilateral pigmentary glaucoma, chronic uveitis, endophthalmitis, non rhegmatogenous retinal detachment, or large vitreous hemorrhages (ocular masquerade syndrome). They can appear as vision alterations, pain and/or episcleral sentinel vessels. In order to confirm the biomicroscopy and ophthalmology diagnosis, the ultrasound A/B scan is useful. This test allows us to check lesion size, spreading and height. The fluorescein angiography helps us delimitate the lesion and its vasculature patterns.
In order to calculate the extrascleral extension, the NMR is more specific than the CAT. Even though 98% does not have diagnostic extension, it is advisable to carry out a general and basic exploration with a complete physical evaluation, a blood count, hepatic markers, a chest X-ray and an abdominal ultrasound. These examinations will be repeated regularly once the diagnosis is confirmed. The differential diagnosis between nevus and melanoma is not always clear but it is very important due to the metastatic disease risk. Growth is the principal metastatic risk factor in these types of lesions because they indicate mitotic activity. Growth risk factors let us anticipate it by determining the malignant potential of the lesions early.
The enucleation is still the chosen therapy for most large melanomas (>15 mm) which invade the optic nerve or produce acute glaucomas. Radiotherapy (brachytherapy/ external beam with charged particles) has shown survival rates up to 5 years compared to the enucleation in medium tumors (10-15 mm) and small tumors (less than 10 mm)
Imagen de melanoma coroideo (izquierda) y aspecto del mismo posterior al tratamiento con braquiterapia (derecha). El área circular marcada corresponde a la localización de una placa de I125 radioactiva
Other possibilities are: observation when the differential diagnosis between nevus and melanoma is difficult; photocoagulation; transpupillary thermotherapy (TTT); surgical resection; exenteration; massive or orbital extrascleral extension, if it exists and chemotherapy if there is a metastatic disease. Less importantly, we find hyperthermia, the photodynamic therapy (PDT) and cryotherapy.
Frequently, therapeutic management leads to a combination of different techniques, such as brachytherapy with 125I together with TTT.