How to Recognize the Signs and Symptoms of Melanoma

Melanoma is the fifth-most-common cause of cancer in the U.S. and, as the American Cancer Society indicates, the rates of melanoma have been rapidly rising in recent decades. Early detection and treatment are especially crucial due to melanoma’s ability to spread rapidly to other organs, but its increasing prevalence puts more demand on specialists.

If a patient is unable to see a dermatologist right away, it’s important for primary care physicians (PCPs) to be able to recognize the signs and symptoms of melanoma skin cancer.

1. ABCDE Rule for Early Diagnosis of Melanoma

   So, what should PCPs look for? Current guidance points to how, while most moles are harmless, the "ABCDE rule" can be helpful in assessing skin lesions:

   • Asymmetry: Most melanomas are asymmetrical. If you drew a line through the mole, the two halves would not match.
   • Border irregularity: The edges of melanomas tend to be uneven—irregular or scalloped instead of smooth.
   • Color is nonuniform: If the color varies, it could be a warning sign. Benign moles are usually a single shade of tan or brown.
   • Diameter greater than 6mm: Assess whether the lesion is larger than 6mm or ¼-inch in diameter, or the size of a pencil eraser—another warning sign. (Melanomas can be smaller, however.)
   • Evolving over time: A mole or skin lesion that is changing in size, shape or color is of concern, as is bleeding, crusting or itching.

   While evidence points to the usefulness of the ABCDE rule as a starting point in advocating for early detection of melanomas, not all melanomas fit the “ABCDE rule.” Staying on top of guidelines for earliest detection of skin cancer is critical to promoting positive patient outcomes.

2. Current Status of Skin Cancer Screening—And Potential Overdiagnosis

   It’s important to note that U.S. Preventative Services Task Force (USPSTF) is currently updating its recommendation for skin cancer screening. Those updated guidelines are still pending, but the need for their re-examination arose to balance caution with clinical burden. More specifically, how effective are screens like the ABCDE rule not just at catching melanoma early—but also at diagnosing accurately, with minimal incidence of false positives?

   While more research is being gathered, PCPs should be aware of the potential for overdiagnosis or overtreatment of skin cancer. Skin screening, as the Texas Surgical Dermatological PA points out, is not a diagnostic tool but rather the first step before requesting further tests. PCPs should make a referral to a dermatologist for such testing. And as of 2016, the USPSTF concluded that the current evidence is insufficient to assess the benefits and harms of visual skin examination by a clinician.

   You might be surprised to learn that a preventative approach to skin cancer includes behavioral counseling. Specifically, the USPSTF recommends that fair-skinned children, adolescents and young adults, aged 10 to 24 years, be counseled about minimizing their exposure to ultraviolet radiation to reduce their risk of developing skin cancer.

Learn more on this topic:

• Screening for Skin Cancer
• USPSTF Recommendation: Behavioral Counseling to Prevent Skin Cancer
• Five-Year Outcomes of a Melanoma Screening Initiative in a Large Health Care System

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