Moles that are not symmetrical, have an uneven border with notched or scalloped edges, or are oddly colored or comprised of many different colors may be indicative of skin cancer, according to the Skin Cancer Foundation. Additional warning signs include moles that have a diameter that is greater than the tip of a pencil or that change in appearance over time.
The warning signs of skin cancer can be remembered by the acronym ABCDE, which stands for asymmetry, border, color, diameter and evolution. Asymmetrical moles do not have matching sides and may indicate skin cancer. The border of cancerous moles generally have uneven edges, especially early on. Noncancerous moles are all a single color, usually brown. If a mole has multiple colors, including different shades of black, tan or brown, it may be malignant. Melanomas may also be blue, white or red, notes the Skin Cancer Foundation.
Small moles are usually not cancerous, but moles larger than 1/4 inch or more in diameter may be malignant. Moles that change or evolve over time may be cancerous. Changes in elevation, color, shape or size or that itch, crust over or bleed can indicate skin cancer. Benign moles will stay the same in appearance over time.
A self-exam monthly can help to identify any suspicious moles. Early detection is key to successful skin cancer treatment.