This is a cancer of the pigment cells (melanocytes) in the skin, and is a dangerous type of skin cancer. It often presents as a dark brown or black skin growth or ulcer. It may look like ordinary moles. But unlike the common mole: -
- it grows more rapidly
- its surface may have varying shades of colour
- its surface may be thick and irregular
- its margin may be irregular
- it may show features of change over time
Melanomas may occur spontaneously, or they may arise from a pre-existing “normal” mole. People born with large moles (giant congenital nevi) or have positive family history of melanoma are at increased risk. Melanoma is more common among Caucasians and less common in Asians and people with a darker skin type. It can occur on any site, including the nails, the palms and soles. Excessive exposure to the sun and a history of sunburns are predisposing factors.
Melanomas have a tendency to spread (metastasise) to surrounding lymph nodes or other parts of the body, leading to morbidity and mortality. As such, early detection and treatment of this condition is important.