A man in his 30s presented with an 18-month history of a painless 3×4 cm mass in his left temporalis muscle which had grown rapidly in the previous month. There were no neurological or ocular symptoms. Past medical history was unremarkable. The mass was excised and showed a metastatic pigmented malignant melanoma. Immunocytochemistry using antibodies HMB45 and MelanA were both positive. Postoperatively, the patient underwent adjuvant radiotherapy.

In search for a primary source an in situ superficial spreading pigmented malignant melanoma of the left leg was removed but was not regarded as the primary lesion. Ophthalmological examination detected a pigmented mass in the inferotemporal quadrant of the left iris/ciliary body with pigmented cells seeding the vitreous. Intraocular pressure of the left eye was markedly raised, and the iris architecture was distorted. Fundoscopy showed multiple hyperpigmented choroidal foci involving the posterior pole of the left eye (fig 1A). …