Marburg, Germany (dpa) - Dangerous moles and birthmarks can be recognized using five criteria, according to a German health and consumer organization based in Marburg.

People can determine whether they need to consult a doctor about a possible case of skin cancer by using five criteria to evaluate their own moles and birthmarks. They are summed up as the ABCDE rules - A for asymmetry, B for border, C for colour, D for diameter and E for embossment.

The criteria indicate when a mole or birthmark should be closely watched. If for example it has an asymmetrical or irregular shape, a jagged border, an uneven colour, a diameter of more than 5 millimetres, if it is embossed or raised above the skin's surface.

Skin cancer often can be avoided by having moles and birthmarks removed.