The most common primary intraocular tumour is the malignant melanoma of the choroid. In white people,the tumour has an incidence of one in 2500 and the average age at presentation is 50 years. The incidence rises with age with a peak at 70 years. However, it is important to appreciate that no age is exempt because choroidal melanomas have been reported in children as young as three years. It is extremely rare in black people. It differs from melanoma of the skin in that it grows more slowly and metastasises late. Most choroidal melanomas are thought to originate from choroidal nevi, which are present in up to 10% of the population. At first, it is seen as a raised pigmented oval area, which can be anywhere in the fundus (Figure 15.1). It is usually brown in colour although it can be amelanotic (or greyish). As the tumour enlarges there might be an associated exudative retinal detachment or, less often, secondary glaucoma. Other associated features might include choroidal haemorrhage and serial photography might be needed to confirm the growth. The usual presentation is with decreased vision or a visual field defect. Diagnosis is confirmed with careful clinical examination, including indirect ophthalmo-scopy and slit-lamp biomicroscopy (contact lens or volk lens examination), fluorescein angiography, ultrasonography and transvitreal fine-needle aspiration in equivocal cases. The most common site for metastases is the liver, so abdominal ultrasound, serum liver function tests, and chest X-ray should be performed at regular intervals. The appearance of liver metastases can be delayed for several years and can occur even if the eye has been removed, signifying micrometastases at the time of presentation. Approximately 40% of patients develop liver metastases within ten years of the initial diagnosis, while the estimated five-year mortality rate for treated medium-size melanomas is between 15% and 23%. The differential diagnosis of choroidal melanoma includes retinal detachment, metastatic choroidal tumours, wet macular degeneration, large choroidal nevi, choroidal haemangioma or choroidal effusion. Historically, treatment involved enucleation (removal of the globe); today, however, many alternative eye-sparing treatments are available, partly dependent on the size and local spread of the tumour. Options include radiotherapy (external plaque, proton beam or helium ion),
laser photocoagulation for small lesions, local resection and transpupillary thermotherapy. Untreated, the tumour can extend into the orbit and provide an unpleasant problem for the patient.
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Complete Guide to Preventing Skin Cancer. We all know enough to fear the name, just as we do the words tumor and malignant. But apart from that, most of us know very little at all about cancer, especially skin cancer in itself. If I were to ask you to tell me about skin cancer right now, what would you say? Apart from the fact that its a cancer on the skin, that is.