Uveal melanoma (UM), a rare cancer of the eye, is distinct from cutaneous melanoma by its etiology, the mutation frequency and profile, and its clinical behavior including resistance to targeted therapy and immune checkpoint blockers.,Primary disease is efficiently controlled by surgery or radiation therapy, but about half of UMs develop distant metastasis mostly to the liver.,Survival of patients with metastasis is below 1 year and has not improved in decades.,Recent years have brought a deep understanding of UM biology characterized by initiating mutations in the G proteins GNAQ and GNA11.,Cytogenetic alterations, in particular monosomy of chromosome 3 and amplification of the long arm of chromosome 8, and mutation of the BRCA1-associated protein 1, BAP1, a tumor suppressor gene, or the splicing factor SF3B1 determine UM metastasis.,Cytogenetic and molecular profiling allow for a very precise prognostication that is still not matched by efficacious adjuvant therapies.,G protein signaling has been shown to activate the YAP/TAZ pathway independent of HIPPO, and conventional signaling via the mitogen-activated kinase pathway probably also contributes to UM development and progression.,Several lines of evidence indicate that inflammation and macrophages play a pro-tumor role in UM and in its hepatic metastases.,UM cells benefit from the immune privilege in the eye and may adopt several mechanisms involved in this privilege for tumor escape that act even after leaving the niche.,Here, we review the current knowledge of the biology of UM and discuss recent approaches to UM treatment.
Ipilimumab, an antibody that enhances T-cell activation, may augment immunogenicity of tumor cells that are injured by radiation therapy.,We hypothesized that patients with melanoma brain metastasis treated with both ipilimumab and radiotherapy would have improved overall survival, and that the sequence of treatments may affect disease control in the brain.,We analyzed the clinical and radiographic records of melanoma patients with brain metastases who were treated with whole brain radiation therapy or stereotactic radiosurgery between 2005 and 2012.,The hazard ratios for survival were estimated to assess outcomes as a function of ipilimumab use and radiation type.,Seventy patients were identified, 33 of whom received ipilimumab and 37 who did not.,The patients who received ipilimumab had a censored median survival of 18.3 months (95% confidence interval 8.1-25.5), compared with 5.3 months (95% confidence interval 4.0-7.6) for patients who did not receive ipilimumab.,Ipilimumab and stereotactic radiosurgery were each significant predictors of improved overall survival (hazard ratio = 0.43 and 0.45, with P = 0.005 and 0.008, respectively).,Four of 10 evaluable patients (40.0%) who received ipilimumab prior to radiotherapy demonstrated a partial response to radiotherapy, compared with two of 22 evaluable patients (9.1%) who did not receive ipilimumab.,Ipilimumab is associated with a significantly reduced risk of death in patients with melanoma brain metastases who underwent radiotherapy, and this finding supports the need for multimodality therapy to optimize patient outcomes.,Prospective studies are needed and are underway.