Melanoma as a model tumour for immuno-oncology.

Melanoma is one of the most aggressive forms of skin cancer. Furthermore, incidence rates are increasing. Until recently, no agent had been shown to improve survival over supportive care and treatment guidelines recommended that patients with metastatic disease were entered into clinical trials. With so few treatment options available, there was a clear need for new, more effective treatments in this setting. Melanoma serves as a 'model' tumour for understanding immunity to cancer. Melanoma tumour-associated antigens were among the first cancer antigens to be identified and classified, with further studies showing that many of these are also expressed by other tumour types. In addition, melanoma regression has been associated with vitiligo, visibly confirming an active role of the immune system in this type of cancer, and spontaneous regression of primary melanomas has also been observed in some cases. These observations, relating to the activity of the immune system in melanoma, provided strong evidence that this tumour would be amenable to immunotherapy, with immunotherapies such as cytokines, adoptive cell transfer and T-cell modulators shown to be an effective therapeutic approach. Against this background, melanoma has long been at the cutting edge of immuno-oncology research and will likely continue to be used as a model tumour to increase our understanding of immuno-oncology and to inform development in other types of cancer.