Uveal Melanoma: Current Insights into Clinical Relevance of Genetic Testing

Uveal melanoma is the most common primary intraocular tumour in Caucasians. There are approximately 500 new cases of uveal melanoma in Germany per year and the incidence rate peaks at the age of 70 years. Half of all uveal melanoma patients develop metastatic disease, which can be observed even many years after successful treatment of the primary tumour. In most cases the liver is the location of first manifestation. Based on the chromosome 3 status uveal melanomas can be divided into two major classes that differ in their metastatic potential. Tumours with a high risk to metastasise usually show monosomy 3, whereas tumours showing disomy 3 rarely metastasise. If a patient wishes to know about his individual risk, prognostic testing of the primary tumour tissue can be performed after obtaining tumour material via transscleral or transretinal biopsy, or by enucleation. To date results of prognostic testing do not influence therapeutic strategies. Recently, major key genes involved in uveal melanoma development, GNAQ, GNA11, BAP1, SF3B1 and EIF1AX, have been identified. Mutation profiling, in addition to chromosomal 3 analysis, will further refine the classification or subclassification of uveal melanomas and will hopefully influence diagnostic or therapeutic concepts. Hereditary mutations in tumour suppressor gene BAP1 are associated with an increased risk for different tumour entities. Detection of germ line mutations in this tumour suppressor gene should implicate further general screening examinations of the patient to be able to detect these tumour entities. Moreover relatives of these patients should be offered a screening for BAP1 mutation.