Melanoma Skin Cancer Guide: Symptoms, Risk Factors & Treatment

Overview

Melanoma is the most serious type of skin cancer, developing in melanocytes: the cells in your skin that produce melanin, the pigment that gives skin its color. While it is far less common than basal cell or squamous cell skin cancer, melanoma is much more likely to spread (metastasize) to other parts of the body if not caught and treated early. When detected at an early, localized stage, melanoma is highly treatable, with a 5-year survival rate of more than 99%.

Signs & Symptoms

The most common sign of melanoma is a new mole, or a change to an existing mole. Use the ABCDE rule to spot potential warning signs: A = Asymmetry (one half of the mole does not match the other), B = Border irregularity (ragged, blurred, or notched edges), C = Color variation (multiple shades of brown, black, red, white, or blue), D = Diameter larger than 6mm (about the size of a pencil eraser, though melanomas can be smaller), and E = Evolving (changes in size, shape, color, or new symptoms like itching, tenderness, oozing, or bleeding). Melanomas can also appear on areas that get little to no sun, including the soles of your feet, under your nails, scalp, groin, or inside your mouth and nose. A new mole that looks very different from all your other moles (the "ugly duckling" sign) is also a warning sign.

Causes & Risk Factors

Melanoma occurs when melanocytes develop DNA damage that causes them to grow out of control. This damage is most often caused by exposure to ultraviolet (UV) radiation from the sun or tanning beds, but other factors also increase your risk:

• Fair skin that burns easily, light eye color, or light hair (blonde, red, or light brown)
• History of one or more blistering sunburns, especially during childhood or adolescence
• Excessive UV exposure from time spent in the sun or use of indoor tanning beds
• Having more than 50 ordinary moles, or many atypical (dysplastic) moles
• Family history of melanoma, or a personal history of skin cancer
• Weakened immune system, such as from an organ transplant or HIV
• Age: Risk increases with age, but melanoma is also one of the most common cancers in people under 30, especially women

Diagnosis

If your dermatologist finds a suspicious mole during a skin exam, they will first use a dermoscope (a special magnifying tool) to examine the mole more closely. If the mole still looks abnormal, a skin biopsy will be performed. During a biopsy, a small sample of the mole is removed with local anesthesia and sent to a lab to check for cancer cells. If melanoma is confirmed, your care team will run staging tests to determine how deep the cancer has grown and if it has spread to lymph nodes or other organs. Never attempt to diagnose a suspicious mole at home, as only a trained dermatologist can confirm if a mole is cancerous, and delaying a professional exam can lead to delayed diagnosis and worse outcomes.

Treatment & Management

Treatment for melanoma depends on the stage of the cancer, how deep it has grown into the skin, and whether it has spread. Early-stage, localized melanoma is usually curable with surgery alone. For advanced or metastatic melanoma, a combination of treatments may be used:

• Wide local excision: Surgery to remove the melanoma and a small margin of healthy skin around it to ensure all cancer cells are removed. This is the standard treatment for early-stage melanoma.
• Sentinel lymph node biopsy: If the melanoma is thick or has high-risk features, the nearest lymph node is removed and checked for cancer cells to see if the cancer has spread.
• Immunotherapy: Medications that help your immune system recognize and attack cancer cells, which have dramatically improved outcomes for advanced melanoma.
• Targeted therapy: Drugs that target specific genetic mutations in melanoma cells, used for certain advanced or metastatic cases.
• Radiation therapy: High-energy rays used to kill cancer cells, sometimes used after surgery to reduce recurrence risk or relieve advanced cancer symptoms.
• Chemotherapy: Less commonly used now, but may be an option for advanced melanoma that does not respond to other treatments.

Living With It

After treatment for melanoma, lifelong follow-up care is critical to catch recurrence or new skin cancers early. You will need regular full-skin exams with your dermatologist, and should perform monthly self-skin checks at home. People who have had melanoma have a higher risk of other skin cancers, so consistent sun protection is a lifelong necessity.