What are the symptoms of skin cancer?

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To detect the warning signs of skin cancer, you should do a self-examination and apply the ABCDE rule that will allow us to detect warning signs: 

  • Asymmetry: when one half of the mole is not the same as the other half
  • Border: when the contour of the mole is uneven, blurred or has jagged edges.
  • Colour: when the colour is not uniform, but has different shades. The most dangerous are red, white or blue on black lesions.
  • Diameter: when at least 6 mm in size.
  • Evolution: the mole undergoes changes in size or shape.

As well as the ABCDE rule, there are other warning signs that can indicate a suspicious lesion. If you have a sore that does not heal, or when there is inflammation beyond the edge of the mole, it is itchy, painful or when changes on the surface of the mole are seen, such as scaling or bleeding.

How to distinguish a mole from a melanoma?

Sometimes, it can be hard to tell a mole from a melanoma. If any anomaly is detected, you should see a dermatologist to diagnose or rule out the pathology. A small number of melanomas start in different places on the skin, such as on the bottom of the foot, under the nails, in the mouth or the coloured part of the eye; so you should pay attention to these areas as well.

Early detection and proper treatment of skin cancer are key to improving prognosis and increasing the chances of a cure.

What is Cancer?

General information about Cancer

Read more

Substantiated information by:

Eugenia Moliner Papell
Josep Malvehy Guilera

Published: 20 February 2018
Updated: 20 February 2018

The donations that can be done through this webpage are exclusively for the benefit of Hospital Clínic of Barcelona through Fundació Clínic per a la Recerca Biomèdica and not for BBVA Foundation, entity that collaborates with the project of PortalClínic.


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