Abstract
Melanoma is a tumor developed by malignancy of melanocytes, being one of the most lethal cancers. Usually, it is associated with exposure to ultraviolet radiations, being most common in the skin, but can also be located extracutaneously as in the digestive tract, leptomeninges or uvea. Histopathologically it presents a phase of radial growth and a vertical one, often accompanied by an intra and peritumoral inflammatory infiltrate. Immunohistochemically, the confirmation of the diagnosis of melanoma should be accompanied by the assessment of proteomic markers of lymphocytic infiltrate such as PD-L1, CD4 and CD8. Those have a role in evaluating the prognosis and a possible prediction of the immunotherapeutic response.