I just wanted to mention that melanoma usually appears on the skin and then if not treated in time will spread to lymph nodes or by way of blood to other organs not vice versa. Once established, late stage, it can then appear on the skin as small red tumors but my point is to treat the area on the leg first. If it indeed is a melanoma and it may not be, removal and staging will then decide what and if further treatment need be rendered. Usually careful follow up is all that is needed if surgically removed in it's early stage. Melanoma usally starts in the skin before spreading internally where it can be treated so there is no reason to do further testing unless it is determined to be a late stage melanoma which I doubt.