Dermatology Services: Melanoma
What is Melanoma?
Melanoma is a disease that develops in melanocytes, the cells that give our skin its pigment, or color. The pigment they produce protects our skin’s basal and squamous cells from the sun’s ultraviolet rays.
Melanoma is the most serious type of skin cancer because it can spread to other parts of the body. If caught early, it can be treated successfully.
The exact cause of melanoma is unclear, but chronic exposure to the ultraviolet (UV) rays from the sun has been shown to increase the risk of developing melanoma. Limiting your exposure to UV radiation, avoiding tanning lamps and wearing broad spectrum sunscreen can help reduce the risk.
But melanoma also can occur in places not exposed to the sun, such as internal organs. Melanoma also can occur in the eyes.
Melanoma is most common in older adults, but it is increasingly being diagnosed in people under age 40, especially women. In fact, women under 50 are more likely to develop melanoma than any other cancer except breast and thyroid malignancies.
Learn the warning signs of melanoma so you can seek a medical diagnosis and get treatment early.
What do I look for?
Remember, melanoma can develop anywhere on or inside your body. Fortunately, the skin can be examined regularly with your own eyes or those of your partner.
Keep an eye out for:
Given that UV rays from the sun are responsible at least in part for the onset of melanoma, these cancers are most commonly found on the head and neck, back, legs and arms.
- An existing mole that is changing in shape, size or color
- A new mole or unusual growth on the skin
It’s much less likely that a melanoma will arise in an internal organ, but should it do so, is more difficult to diagnose early.
In people with darker skin types, melanomas occur more frequently on the soles of the feet, palms of the hands and fingernail beds, areas that don’t traditionally see as much sunshine.
Moles — what’s normal, what's not?
Most of us have between 10 and 30 moles on our skin before age of 50. And most are benign.
Normal moles are generally oval or round patches of 6 millimeters or less in diameter — about the size of a pencil eraser. They are unchanging in shape and size and are of uniform color, such as tan, brown or black, and have a distinct border.
But when new moles appear or existing moles change in size or shape, use the A-B-C-D-E rules as your guide:
- A for asymmetry — Moles of irregular shapes, where the two halves of a mole are not identical may be of concern. If one mole is quite different from the others — we call this the Ugly Duckling — it could be a sign of melanoma.
- B for irregular border — Moles with notched or scalloped edges, where borders are irregular are cause for concern.
- C for Color — Moles with varying colors or that are changing in color, including loss of pigmentation, should be examined further.
- D for Diameter — Moles that are fast growing and those that are larger than 6 millimeters may be cause for concern. New melanomas often start off much smaller than 6 millimeters, but are less noticeable.
- E for Evolving — Moles that are evolving or changing in color, size, shape, sensation , or even bleeding, should be examined by a doctor..
Cancerous moles or skin patches can vary greatly in appearance — and some of the changes may be very subtle.
Check your skin regularly
If you don’t look, you won’t see! It’s useful to examine your skin on a monthly schedule, such as the first Monday of each month.
A full skin exam involves more than just looking over the back, neck, chest, torso, arms and legs. It also includes checking the clefts between your toes and fingers, your buttocks and genitals. The latter is often neglected by physicians while doing a ‘full skin exam.
If it is more convenient, some women may prefer to have their gynecologist examine them for pigmented lesions in the genital area, especially the vaginal mucosa.
Examine fingernails, especially if you have darker skin, for a acral-lentiginous melanoma growing beneath the nail. Also check the bottoms of the feet and inside the mouth.
Don't forget to examine your eyes, particularly the whites, for signs of a growing dark spot. However, many symptoms of melanoma of the eye mimic other eye problems, so an examination by an ophthalmologist may be needed.
If you notice any of these changes, consider making an appointment with your primary care physician or dermatologist.
To make an appointment with one of our UC Irvine Health skin cancer experts, please call 949-824-0606. Our dermatologists see patients in Costa Mesa, Irvine, Orange and Tustin.