The ABCDE Test for Skin Cancer

The ABDCE test is a diagnostic test to find out if a mole or a spot on your skin is melanoma. When in doubt, consult your doctor.
The ABCDE Test for Skin Cancer

Last update: 04 May, 2022

The ABCDE test is a technique used by dermatologists to analyze moles and skin lesions that could be cancerous.

According to a study by the National Cancer Institute, skin cancer is the third most common type of cancer. The same study indicates that this disease mainly affects people with light skin and claims that in more than 90% of cases, direct ultraviolet radiation is directly responsible for it.

That said, preventive habits such as self-assessment and annual check-ups play a very important role in the fight against this type of cancer. Also, the study indicates that 90% of early detected skin cancer cases can be cured.

Therefore, the ABCDE test is an important diagnostic tool. The words asymmetry, border, color, diameter, and evolution are used for the various steps of this test. With this system, doctors can differentiate moles from harmless spots and try to prevent what’s one of the most aggressive and dangerous types of skin cancer: melanoma.

The ABCDE Test: What Should You Look for in a Mole?

A freckled person's back.
Early diagnosis of skin cancer delays a lot of otherwise early deaths.

Certain moles are more likely to become cancerous. This could happen with those moles that you’ve always had as well as with newly formed ones. However, the latter are more likely to become melanoma.

If you can’t tell which are regular moles and which could be cancerous, you can get an idea by learning the ABCDE test:

A for Anomaly

The first letter tells us that we have to look at the shape of the moles. Those that are harmless are usually round and symmetrical. That is, if you were to fold them, then both halves would overlap.

On the contrary, melanomas tend to be asymmetric and have no specific shape.

B for Border

A mole with an irregular shape. The perfect candidate for an ABCDE test.
Irregular shapes or color changes may be indicative of skin cancer.

The second thing to look for is how regular the edges of a mole are. This feature is another clue to know if it can be melanoma.

When the edges of a mole are irregular or have jagged, sharp, wavy, ill-defined boundaries, then the mole is likely to be cancerous.

You may also be interested in: Is Melanoma the Only Serious Type of Skin Cancer?

C for Color

Harmless moles present the same hue throughout their pigmented area.

However, if you find a spot that has a variety of color from one area to another (brown or black, and sometimes even white, red or blue), then it’s possible that your mole is melanoma.

D for Diameter

Another important thing to keep in mind is the size of the mole. If its diameter (the distance from one end of the mole to the opposite side), is 1/4 inch or more, then the mole may be melanoma. Benign or harmless moles are usually small.

A good measuring device for measuring moles is the erasers that many pencils have on the end. It’ll give you a good visual, as the size of the eraser is about 1/4 inch.

E for Evolution

Finally, the evolution of a certain mole must be considered. If it presents progressive changes in color and size or has other spots around it, then it’s a clear sign that it could be a melanoma.

ABCDE Test: Conclusion

You can do this quick test on your own in addition to your annual skin check-up to prevent any type of problem. If you find an anomaly, don’t hesitate to consult your doctor before the year is up.

As a complement to the ABCDE test and to know if there are serious health risks, there are other changes in the spots or moles that may be the beginning of melanoma.

Some of these changes are:

  • Swelling
  • Itching
  • Bleeding

Skin Cancer Prevention

A fashionable woman applying sun lotion to her shoulder.
One step in the prevention of skin cancer is to apply a sunscreen that’s suitable for your skin type.

The main preventive measure is to avoid sun exposure and artificial sources of UVA rays. It’s important to highlight the importance of avoiding tanning beds, as well as using a suitable amount of sunscreen every day.

Here are some steps you should take to try to prevent skin cancer:

  • Don’t expose yourself to the sun without protection. It should contain at least 30 SPF (sun protection factor), although in this case, 50 SPF is more effective.
  • Avoid sunbathing between noon and 5 pm, especially during summer, which tends to be the hottest time of the year.
  • Don’t overexpose children under three years of age to the sun. If they must be outside, then protect them with hats and sun lotion in accordance to their skin type.

  • Schadendorf, D., van Akkooi, A. C. J., Berking, C., Griewank, K. G., Gutzmer, R., Hauschild, A., … Ugurel, S. (2018). Melanoma. The Lancet.
  • Castañeda, Paola Eljure, J. (2016). El cáncer de piel, un problema actual. Revista de La Facultad de Medicina de La UNAM.
  • Merino, M. (2005). Prevención del cáncer de piel y consejo de protección solar. Revista Pediatría de Atención Primaria.