Melanoma is the most aggressive form of skin cancer, and the most rapidly expanding cancer in terms of worldwide incidence.Chemotherapeutic approaches to treat melanoma have been uniformly disappointing.Previous studies in mice have demonstrated that a high diluted complex derivate from Calcarea carbonica (MS) activated maerophages, increased NO production, increased the number of CD45R+ cells in bone marrow and CD8+ cells in mesenteric lymph node, and stimulated the tumoricidal response of activated lymphocytes against B 16F 10 melanoma cells in vitro.Here we described the in vitro inhibition of B16F 10 cells in the invasion assay by scanning electron microscopy and the in vivo anti-metastatic potential of M8 inhalation treatment in the B 16F 10 lung metastasis model.The lungs were processed to be histologicaly analyzed and immunohistochemistry was performed to detect and quantify Pertecan, a proteoglycan involved in adhesion and metastasis.