Most of us know that being out in the sun can damage the skin. One of the health issues that can develop from prolonged sun exposure is skin cancer. Melanoma, the most aggressive form of skin cancer, is diagnosed in nearly 100,000 people in the U.S. each year, as well as more than 324,000 people worldwide.
This cancer commonly develops in people who have had a lot of sun exposure, but it can affect anyone. When melanoma is detected early, treatments are more effective. Therefore, it is important to talk to your doctor about any new or changing spots that appear on your skin.
What are the symptoms of melanoma?
Melanoma usually looks like an abnormal bump, sore, or mole. Experts use the acronym “ABCDE” to describe when a skin spot may be melanoma:
- Asymmetry — Half of the spot looks very different than the other half.
- Border — The spot is not a perfect circle; it has uneven or jagged edges.
- Color — The spot contains multiple different colors.
- Diameter — The spot is pea-sized or larger.
- Evolving — The spot’s appearance has recently changed.
If you notice any of these potential warning signs, talk to your doctor or to a dermatologist. A health care provider can carefully examine the spot and take a biopsy (remove part of the spot and look at it more carefully under a microscope).
Types of melanoma
The exact appearance of a cancerous skin spot depends on what type of melanoma it is. There are several types of melanoma:
- Superficial spreading melanoma — The most common type of melanoma—superficial spreading melanoma—tends to be flat, have irregular borders, and contain different shades of brown and black.
- Nodular melanoma — This type of melanoma starts spreading quickly. It is often raised from the surrounding skin and dark in color.
- Acral lentiginous melanoma — This form of melanoma can develop on the palms, soles of the feet, or under the finger or toe nails.
- Lentigo maligna melanoma — Large, flat growths that appear on areas of skin that have become damaged may be lentigo maligna melanomas.
- Amelanotic melanoma — Melanomas that are amelanotic, or “without melanin,” are pink or skin-colored bumps.
- Desmoplastic melanoma — This rare type of melanoma is most often found on the skin of the head or neck in elderly adults.
What causes melanoma?
Melanoma forms due to gene changes in skin cells. Genes serve as instructions that control how a cell functions. Gene changes, or mutations, cause the cell to begin growing out of control.
One of the main causes of gene mutations in skin cells is exposure to ultraviolet (UV) light from the sun. UV light is a type of radiation that can damage DNA (the material that makes up the cell’s genes). Cells can’t “read” damaged DNA correctly and may start acting abnormally.
Some risk factors can increase your chances of being diagnosed with this cancer. You may be more likely to develop melanoma if you have:
- Lighter-colored skin
- Green or blue eyes
- Blond or red hair
- A job or routine that leads you to spend a lot of time in the sun
- A history of using tanning beds
- A home at a high altitude or in an area that gets a lot of sun
- A history of getting severe sunburns as a child
- A weak immune system due to health conditions or medications
Most people who develop melanoma don’t have a family history of the condition. However, there are some cases in which genes that increase melanoma risk are passed down through families.
Potential melanoma treatments
Usually, melanomas are first treated with surgery, during which a doctor will try to remove all of your cancer and some of the surrounding skin. If a lot of skin has been taken, the surgeon may take skin from another part of your body and use it to replace some of the skin that was removed.
If there is a chance that there are some cancer cells still remaining in your body, your doctor may recommend other treatments, such as:
- Chemotherapy — Medications that kill cancer cells or prevent them from growing
- Targeted therapy — Drugs that recognize and attack cancer cells while largely leaving normal cells alone
- Immunotherapy — Medications that boost the immune system’s ability to fight cancer
- Radiation therapy — High-energy waves or particles that damage and kill cancer cells
Melanoma survival rates
If you are diagnosed with melanoma, your outcome is largely based on how much cancer is present in your body and how far is has spread. Early-stage melanomas that are caught soon after they form can be more easily treated than later-stage melanomas:
- People with localized melanoma (cancer cells are only found in a single location) are 99.5% as likely to be alive after five years, compared to people without this cancer.
- People with regional melanoma (cancer cells have spread to nearby areas) are 70.6% as likely to be alive after five years as people who don’t have the cancer.
- People with distant melanoma (cancer cells have spread around the body) are 31.9% as likely to be alive after five years, compared to those who haven’t been diagnosed.
If you are worried about melanoma risk, talk to a dermatologist. This health care provider can screen your skin for potential signs of cancer and help you understand the importance of protecting yourself from the sun in order to reduce your chances of developing melanoma.
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