A mole, also known as a nevus, represents a common skin growth composed of clusters of pigment-producing cells called melanocytes. Most people develop moles during childhood and adolescence, typically having between 10 to 40 by adulthood. Discovering a scab on an existing mole can cause alarm. While scabbing can arise from various reasons, some are benign and others may require medical evaluation.
Typical Causes of Scabbing
A common reason a mole might scab is due to trauma or injury. Accidental scratching, rubbing from clothing or jewelry, or minor bumps can irritate a mole, leading to a break in the skin. The body then forms a scab to protect the injured area as new skin regenerates.
Certain benign moles or other common skin growths, like seborrheic keratoses, can undergo changes that lead to temporary scabbing. These changes might include itching, inflammation, or flaking, which can cause the surface of the growth to become crusty. Such instances usually resolve on their own as the skin heals.
When to Be Concerned
Scabbing on a mole can indicate more serious underlying conditions, particularly skin cancer. Dermatologists often use the “ABCDEs” to identify suspicious moles that might be melanoma, a severe form of skin cancer. Asymmetry means one half of the mole does not match the other, while border irregularity refers to uneven, notched, or poorly defined edges. Color variation involves multiple shades of tan, brown, black, or even areas of white, red, or blue within the same mole. A diameter larger than 6 millimeters, roughly the size of a pencil eraser, is another warning sign.
The “E” in ABCDE stands for Evolving, which is relevant when a mole scabs. An evolving mole changes in size, shape, color, or symptoms over time. This evolution can include the development of a scab, bleeding, oozing, or a sore that does not heal.
Beyond melanoma, other types of skin cancer, such as basal cell carcinoma (BCC) and squamous cell carcinoma (SCC), can also manifest as persistent, non-healing sores or scabs. BCCs often appear as small, pearly, or waxy bumps that may bleed easily. SCCs can present as red, scaly patches or open sores that may crust over. These non-melanoma skin cancers may also exhibit persistent bleeding, tenderness, or pain.
Other concerning signs include a scab that does not heal within a few weeks, or repeatedly scabs and then reopens. Rapid growth of the mole, along with tenderness or inflammation, also warrants prompt medical evaluation. New moles appearing in adulthood, especially with concerning characteristics, should also be examined by a healthcare professional.
Next Steps
For a mole with a minor scab from an obvious injury and lacking concerning signs, general care involves keeping the area clean and protected. Avoid picking at the scab to allow natural healing. Applying petroleum jelly can help keep the area moisturized and aid healing.
If the scab on a mole does not heal within a few weeks, recurs, or is accompanied by any worrying signs, seeking professional medical advice is strongly recommended. This includes changes in size, shape, color, bleeding, pain, or itching. Any doubt or anxiety about a mole’s appearance or changes should prompt a visit to a doctor.
During a medical evaluation, a doctor will perform a visual examination of the mole, often using a dermatoscope. If suspicion of malignancy remains, a biopsy may be recommended for laboratory analysis. Various biopsy methods are used, performed under local anesthesia. Early detection of skin cancer significantly improves treatment outcomes.