Origins of melanoma
Melanoma begins in melanocytes cells (the cells that create pigment) in the deepest layer of skin, also known as the hypodermis or subcutaneous tissue. When these cells become damaged, mutations can occur and the mutated cells can reproduce themselves rapidly, eventually forming a tumor and taking over surrounding tissues.
Where melanoma occurs
Melanomas can develop anywhere on the body, including areas not exposed to the sun, such as inside the mouth or the palms of the hands; however, areas regularly exposed to the sun, like the back, legs, arms and face, are at greater risk for developing melanoma. Men are more likely to develop melanomas on their back, trunk or head and neck while women are more likely to develop them on their arms and legs.
A study in the Journal of American Academy of Dermatology found that melanomas in blacks, Asians, Filipinos, Indonesians, and native Hawaiians most often occur on non-exposed skin with less pigment, with up to 60-75 percent of tumors arising on the palms, soles, mucous membranes and nail regions.
> Learn more about these rarer symptoms of melanoma.
How melanoma first appears
Melanomas can develop from existing moles or skin growths or start as a new growth. That’s why it’s important to regularly check your whole body for new moles and growths or changes in existing moles. There are several tell-tale symptoms that indicate if a mole or growth may be cancerous. These are summarized in the ABCDE method of detection.
The ABCDE checklist:
Dermatologists identify melanoma symptoms using the ABCDE method. This method shows you which signs to look out for when examining suspicious moles, spots or growths on your skin.
- Asymmetrical – Melanomas are distinctly asymmetrical
- Border – melanomas have uneven borders
- Colours – melanomas will contain at least two distinct colours
- Diameter – melanomas are bigger than ¼ inch across
- Enlargement – melanomas grow in size over time
The evolution of your mole(s) has become the most important factor to consider when it comes to diagnosing a melanoma. Knowing what is normal for YOU could save your life. If a mole has gone through recent changes in color and/or size, bring it to the attention of a dermatologist immediately.
Read more: ABCDE Melanoma self check
If you notice one or more of these melanoma symptoms, be sure to schedule an appointment with your doctor or dermatologist right away to get the mole or mark checked out.
Other warning signs
Other warning signs of melanoma include if a mole or growth:
- develops a crust or a scab
- sometimes bleeds or oozes
- is itchy
- feels tender
- gets bigger or swells
- has a changing surface texture, such as becoming scaly or developing a lump
Learn more about how melanoma spreads.