Melanoma is a rare form of skin cancer that accounts for the vast majority of skin cancer deaths. A person's risk of developing the disease involves a combination of modifiable and inherited or genetic factors. Overall, melanoma has a high cure rate, including 99% of the cancers that are identified, diagnosed, and treated early.
The 5-year survival remains low for melanoma that has metastasized or spread to other sites in the body, underscoring the importance of early diagnosis and treatment.
How Does Melanoma Occur?
Melanoma originates in skin cells known as melanocytes, which produce the substance known as melanin that determines a person's skin color. The major risk factor for melanoma is exposure to sunlight and other forms of ultraviolet (UV) light, such as tanning beds and booths. UV light alters the genetic makeup of melanocytes and the substances they produce to set in motion a chain reaction of biological processes that lead to cancer formation.
Melanoma occurs in men and women and in people with all skin types and colors, although the cancer occurs far more often in white people, especially older white men.
People who have fair skin, red or blond hair, and freckles have a higher risk, as do people who tend to sunburn instead of tan. Frequent sunburn at an early age, chronic exposure to sunlight and other forms of UV light, presence of numerous moles, and a family history of melanoma also are associated with an increased risk of the cancer.
How Do I Recognize Melanoma?
Melanomas can occur anywhere on the body, including areas that have little or no sun exposure, such as the soles of the feet.
The most common locations are the trunk or torso, upper back, arms and lower legs, face, and neck -- areas routinely exposed to sunlight. Most melanomas have a dark brown or black color. They may resemble large moles or even originate within an existing mole.
The (AAD) has promoted the ABCDE approach to recognizing melanoma:
- A - Asymmetry: one half of the melanoma does not match the other
- B - Border irregularity: Ragged edges, notched or blurred appearance
- C - Color: Not uniform in color, different shades of brown or tan, specks of red, white, or blue
- D - Diameter: Size that is usually, but not always, larger than 6 mm (about 1/4 in.) in diameter
- E - Evolving: Visually different from other moles or skin lesions; appears to be changing in size, shape, or color
Frequent itching, oozing, or bleeding from a mole or other skin growth should also be considered suspicious. Melanomas typically are not painful.
How Is Melanoma Diagnosed?
A dermatologist or other physician should examine any suspicious mole or other skin growth. If the exam does not rule out melanoma or another form of skin cancer, the doctor may perform a biopsy or refer you to a specialist for the biopsy. During a biopsy, the doctor will remove a portion of or possibly the entire lesion and send it to a laboratory for analysis.
Alternatives to surgical biopsy have been developed but are not as widely available. A technique called reflectance confocal microscopy is a type of imaging that can allow a doctor to look through the different layers of the skin.
Additionally, a patch test can be used to remove a layer of skin cells for laboratory analysis. However, even if one of these alternatives is used to evaluate a suspicious skin growth, a biopsy remains the standard for a definitive diagnosis.
What If I Have Melanoma?
Fortunately, most melanomas are diagnosed early and are associated with a 99% cure rate, usually with surgery alone to remove the skin cancer. Depending on the size, depth, and other characteristics of the melanoma, additional ("adjuvant") treatment might be recommended. Targeted agents and immunotherapy, instead of chemotherapy -- in contrast to the situation with other tumors -- are used to decrease the risk of recurrence after surgery.
Fewer than 5% of melanomas have spread to other sites in the body (metastasized) at diagnosis. In those cases, targeted drugs and immunotherapy have greatly increased survival in metastatic melanoma, and more patients than ever are living 5 years or longer after diagnosis of metastatic disease.
For additional information about melanoma, the AAD and the have helpful resources.
"Medical Journeys" is a set of clinical resources reviewed by physicians, meant for the medical team as well as the patients they serve. Each episode of this 12-part journey through a disease state contains both a physician guide and a downloadable/printable patient resource. "Medical Journeys" chart a path each step of the way for physicians and patients and provide continual resources and support, as the caregiver team navigates the course of a disease.