[header] How to prevent melanoma [title] Limit your exposure to the sun. [step] Melanoma begins in your body's melanocytes (the cells responsible for producing your body's pigment or color). Ultraviolet rays from the sun interact with these melanocytes, causing them to produce a dark protective pigment. 
If your melanocytes are overexposed to ultraviolet rays, melanoma can begin to form. Malignant tumors are a result of cumulative cellular effects of uv light and inability of skin to mount a defense to it.