Melanoma: The small percentage with a big impact

A guest piece by Moorhead High School student Sienna Lee (supervised by Dr. Daniel Dong Joo Kim, M.D., FAAD, clinical associate professor at UND and chair, Essentia Health Fargo Department of Dermatology)

As summer comes to an end, remember that the American Cancer Society estimates approximately 8,400 deaths from melanoma in 2025.

Although melanoma is the most dangerous form of skin cancer, it is often underestimated because it is relatively rare, accounting for one percent of skin cancers. Even so, the cancer’s aggressive malignancy, which arises from the pigment-producing cells of the skin known as melanocytes, causes the vast majority of skin cancer deaths in the United States.

Most melanomas occur on sun-exposed sites — the back, legs, arms, and face. However, cancers can also present in unexpected places, including between toes, under fingernails or toenails, on the palms or soles (acral lentiginous melanoma), or in mucosal areas such as the mouth, nose, or genital tract (mucosal melanoma). These less-visible sites are often diagnosed late due to reduced awareness and delayed detection.

Likewise, most adults have multiple moles – or nevi (the plural for nevus, the technical term for a skin mole). Counts vary, but many individuals have between 10 and 40 moles. While most moles are benign, approximately one in four melanomas develop from a pre-existing mole. The challenge is early recognition.

Health providers typically utilize the ABCDE mnemonic device as a simple, evidence-based screening tool when examining moles:

• Asymmetry – One half doesn’t match the other
• Border – Irregular, ragged, or blurred edges
• Color – Varied shades or unusual pigmentation
• Diameter – >6 mm (larger than a pencil eraser)
• Evolving – Change in size, shape, or color over time

As readers may know, common risk factors for skin cancer include UV Exposure (cumulative sun exposure and especially blistering sunburns during childhood or adolescence are major contributors); use of indoor tanning devices/beds; fair skin, freckles, light-colored eyes, and red or blond hair; family and/or personal history of skin cancer. Note that rare cancer subtypes, such as acral lentiginous and mucosal melanomas, are less common but more likely to be diagnosed at advanced stages.

Early detection is the single most important prognostic factor. For localized disease caught early, five-year survival rates exceed 97–99%. Treatment is typically surgical excision with clear margins. The case is different with more advanced disease, which may have spread to lymph nodes or distant organs and requires more complex interventions, including immunotherapy, targeted agents, and radiation. Prognosis decreases substantially with metastatic spread.

To prevent such spread, providers recommend: monthly self-checks (with mirrors or assistance for hard-to-see areas); annual full-skin exams from a health provider, especially for high-risk patients; sun protection broadly defined (avoiding peak UV hours of 10 a.m. to 4 p.m. and use broad-spectrum SPF 30+ sunscreen daily); and wearing protective clothing, wide-brimmed hats, and UV-blocking sunglasses. And avoid use of tanning beds.

All of that said, enjoy the late summer sun safely before winter sets in!