Malignant melanomas may arise in the uveal tract, the conjunctiva, the skin of 
the eyelid, or the orbit. Risk factors so far identified include pre-existing 
choroidal naevi for uveal melanomas, primary acquired melanosis (PAM) for 
conjunctival tumours, and ocular and oculodermal melanocytosis for uveal and 
orbital lesions. The atypical mole syndrome (AMS) is associated with uveal and 
conjunctival melanomas, especially when the ocular lesions are multiple or 
familial. AMS patients should be screened for ocular melanomas. Conjunctival 
melanomas are managed by excision with or without adjunctive beta-irradiation. 
Circumscribed tumours have a better prognosis than diffuse and multifocal 
lesions arising in acquired melanosis and attempts should be made to limit the 
progress of the latter variant of the disease by treating PAM with cryotherapy. 
The most significant prognostic factor in uveal melanoma is the size of the 
tumour at presentation. Early dissemination is the rule and every effort should 
be made to distinguish a melanoma from a naevus as soon as possible. Small and 
medium-sized melanomas respond well to focal treatments chosen according to the 
size and location of the tumour. The techniques employed include 
photocoagulation, radioactive plaque therapy, proton beam radiotherapy and 
surgical resection.