this likelihood of metastasis for an individual patient. The average survival time after diagnosis of liver metastases depends on the extent of systemic spread. The disease-free interval, the performance status, the liver substitution by metastases and the serum level of lactic dehydrogenase are the most important prognostic factors for metastatic uveal melanoma. There is currently no cure for metastatic uveal melanoma. Treatment The treatment protocol for uveal melanoma has been directed by many clinical studies, the most important being The Collaborative Ocular Melanoma Study (COMS). The treatment varies depending upon many factors, chief among them the size of the tumor and results from testing of biopsied material from the tumor. Primary treatment can involve removal of the affected eye (enucleation); however, this is now reserved for cases of extreme tumor burden or other secondary problems. Advances in radiation therapies have significantly decreased the number of patients treated by enucleation in developed countries. Plaque brachytherapy The most common radiation treatment is plaque brachytherapy, in which a small disc-shaped shield (plaque) encasing radioactive seeds (most often iodine-125, though ruthenium-106 and palladium-103 are also used) is attached to the outside surface of the eye, overlying the tumor. The plaque is left in place for a few days and then removed. The risk of metastasis after plaque radiotherapy is the same as that of enucleation, suggesting that micrometastatic spread occurs prior to treatment of the primary tumor. Proton therapy Proton therapy delivers powerful doses of radiation to the tumor while sparing surrounding healthy eye tissue. The treatment is also effective at controlling tumor growth and maintaining a patient's natural eye. Immunotherapy On January 25, 2022, the FDA approved tebentafusp (Kimmtrak) for adult HLA-A*2-positive patients with metastatic uveal melanoma. Approval was based on the IMCgp100-202 trial (NCT03070392), which compared tebentafusp with investigator's choice of either dacarbazine, pembrolizumab or ipilimumab. Patients lived a median of 16 months when treated with investigator's choice of therapy, compared to a median 21.7 months with tebentafusp. This translated in a 49% reduction in the risk of death. Overall survival after one year of treatment was 59% in the control group, versus 73% in the tebentafusp group. Other Other modalities of treatment include transpupillary thermotherapy, resection of the tumor, gamma knife stereotactic radiosurgery, or a combination of different modalities. Different surgical resection techniques can include trans-scleral partial choroidectomy and transretinal endoresection. A 2017 analysis of genomic data led to a new