Spontaneous regressions of metastatic melanoma are rare, but several cases have been described in the literature. Although the mechanism of the phenomenon is not well understood, it is postulated that an activation of the immune system is behind it. Here we report the case of a patient with metastatic melanoma that, without any treatment, regressed spontaneously. The patient presented psoriasis (a disease of the skin related with autoimmunity) linked with HLA-Cw6. We review the literature and hypothesize with the possible relationship between psoriasis, HLA-Cw6 and the spontaneous regression.