A new or changing spot can be difficult to judge at home. The ABCDE clues are a way to notice features worth bringing to a clinician's attention. They are not a test that proves or excludes melanoma.
If you see a concerning change, arrange medical assessment rather than repeatedly comparing the spot with internet photographs. Skin cancer can occur in people of every skin color, and its appearance is not always the same.
What the letters describe
The American Academy of Dermatology's ABCDE guide describes:
- A, asymmetry: one half looks different from the other.
- B, border: the edge is irregular or poorly defined.
- C, color: the spot contains differing colors.
- D, diameter: melanomas may be larger than a pencil eraser, but they can be smaller.
- E, evolving: a spot changes in size, shape, color, or behavior.
These are observation prompts. A small spot is not automatically safe, and a spot does not need to show every feature before you ask about it. Another useful concern is a spot that looks unlike your other spots.
Include symptoms and location
Tell the clinician about itching, bleeding, pain, or a sore that does not heal. Note when you first noticed the spot and whether it has changed. Changes on areas you rarely see, including the soles, scalp, or beneath a nail, also deserve attention.
NCI's melanoma information explains that examination and, when appropriate, biopsy are used to establish a diagnosis. An app, photograph, or home inspection cannot replace that process.
Do not scrape, burn, or use a home removal product on a suspicious spot. Removing its visible surface can complicate later assessment and does not establish what it was.
Make an appointment request useful
When contacting the clinic, describe the location and change in plain language. For example: “A spot on my left calf has become darker and started bleeding without an obvious injury.” Ask how soon it should be evaluated and what to do if it changes while you wait.
If you have a previous melanoma, immune suppression, or a strong family history, mention that. The clinic can use your history when deciding the appropriate appointment.
If access is difficult, contact your primary-care clinician for help arranging an assessment. A request should not depend on your ability to name the diagnosis.
Use photographs as a record
If the clinic wants photographs, take them in good light without filters. Include a view showing the location and a closer view. Ask the office how to send them securely.
A dated photograph can help show a change, but lighting, distance, and angle can make comparisons misleading. Do not use a lack of obvious photographic change as a reason to cancel an advised examination.
If a helper photographs an area you cannot see, tell them which spot you mean. Keep a simple location note so similar-looking spots are not confused.
Questions for the skin examination
- Which spot concerns you, and why?
- Do you recommend a biopsy or another follow-up?
- How and when will I receive results?
- Should I check other areas or arrange a full skin examination?
- What changes should prompt an earlier call?
Before leaving, make sure you can identify the exact spot the clinician assessed. If monitoring is advised, request a clear interval and contact plan. The purpose of noticing changes is to obtain an informed examination, not to become your own diagnostician.
