Moles are common skin growths, and it’s natural to wonder about their nature, especially when new ones appear. Understanding them can help distinguish harmless growths from those requiring medical attention.
What Are Moles?
Moles, also known as nevi, are clusters of melanocytes, skin cells that produce melanin, the pigment responsible for skin color. These clusters form visible growths. Most adults typically have between 10 and 40 moles.
Common moles (nevi) are usually small, symmetrical, and uniformly colored, ranging from pink to tan or brown. Atypical moles, or dysplastic nevi, differ from common moles; they can be larger than 5 millimeters, have irregular borders, and display varied coloration. While most moles are benign, atypical moles may indicate an increased risk of developing melanoma. Congenital moles are present at birth or appear within the first year of life, occurring in about 1% to 2% of the population. These moles also vary in size and color, and while most are benign, larger congenital moles have a slightly higher risk of developing into melanoma later in life.
New Moles and Cancer Risk
Not all new moles are cancerous, and the vast majority are benign. While many moles develop during childhood and adolescence, new moles can continue to appear into adulthood, often influenced by hormonal changes, such as during pregnancy. Most moles that appear after age 30 should be monitored.
It is important to monitor new moles because melanoma, a serious form of skin cancer, can sometimes arise from a new mole rather than an existing one. About 70% to 71% of melanomas develop as new spots on previously normal skin, while less than 30% originate from existing moles. Melanomas that appear as new growths may also be thicker and potentially have a less favorable prognosis. Therefore, observing any new growths is crucial for skin health.
Signs of Concern
Recognizing specific characteristics can help identify moles that may be concerning. The “ABCDEs” of melanoma detection provide a helpful guide for self-examination:
- Asymmetry: One half of the mole does not match the other half in shape or appearance.
- Border irregularity: Edges are ragged, notched, or blurred, unlike the smooth, distinct borders of common moles.
- Color variation: The mole has uneven coloration, including shades of black, brown, and tan, or even areas of white, gray, red, pink, or blue.
- Diameter: A mole larger than 6 millimeters (about 1/4 inch, the size of a pencil eraser) should be viewed with caution, although melanomas can sometimes be smaller.
- Evolving: Any change in size, shape, color, or elevation of a mole over weeks or months, or any new symptoms like bleeding, itching, or crusting.
These ABCDE criteria serve as warning signs, prompting further evaluation.
When to See a Doctor
It is advisable to seek professional medical advice from a dermatologist if any mole, whether new or existing, exhibits one or more of the ABCDE characteristics. Additionally, any mole that is itching, bleeding, or painful warrants immediate medical attention. Prompt detection of melanoma significantly improves the chances of successful treatment.
During a visit, a dermatologist will typically perform a visual examination of your skin, using a dermatoscope to look more closely at suspicious moles. If a mole is deemed suspicious, a biopsy will be performed. This involves removing a small sample of the skin growth for microscopic analysis. Different types of biopsies, including shave, punch, and excisional, are chosen based on the mole’s characteristics. The procedure usually involves local anesthesia to numb the area, making it largely painless.