Benign and malignant lesions of skin

Melanoma is the most serious cancer of the skin. Possible signs of melanoma include, but not limited to, a change in the appearance of a mole or pigmented area.


A doctor should be consulted if any of the following problems occur:

  • A mole that:

◦    changes in size, shape, or color

◦    has irregular edges or borders

◦    is more than 1 color

◦    is asymmetrical (if the mole is divided in half, the 2 halves are different in size or shape)

◦    itches

◦    oozes, bleeds, or is ulcerated

  • Any Change in pigmented (colored) skin.
  • Satellite moles (new moles that grow near an existing mole).

Some refer to “ABCD” rule of melanoma:

  • A: asymmetry – one half of the mole does not match the other half.
  • B: border irregularity – the edges of the mole are ragged or notched.
  • C: color – the color of the mole is not the same all over. There may be shades of tan, brown, or black, and sometimes patches of red, blue, or white.
  • D: diameter – the mole is wider than about 1/4 inch (although doctors are now finding more melanomas that are smaller).

Unfortunately, some melanomas do not fit the descriptions above, and it may be hard to tell if the mole is normal or not, so you should show your doctor anything that you are unsure of.