Melanoma is a type of skin cancer. It is most common in the skin. However, it can also form in the eyes, digestive system, nails, or lymph nodes.
Melanoma is more likely to spread to other parts of the body and be fatal. Early treatment is important.
Cancer happens when cells divide without control or order. These cells grow together to form a tumor. They can invade and damage nearby tissues. They can also spread to other parts of the body.
It is not clear what causes changes in the cells. It is likely due to genes and environment.
Melanoma is more common in men and those aged 40 to 60 years old. However, younger people can also get it.
Things that raise the risk are:
Melanomas are not usually painful.
Symptoms may be a change in the size, shape, color, or feel of an existing mole. Melanoma may also appear as a new, dark, discolored, or abnormal mole.
Signs that a mole may be melanoma are (ABCDE rule):
Some melanomas do not fit the ABCDE rule.
The doctor will ask about symptoms and past health. A physical exam will be done. The doctor will look at the skin and moles. A tissue sample of the area will be taken and tested for cancer.
The doctor may also check lymph nodes. Swollen lymph nodes could mean melanoma has spread. A sample of lymph node tissue may also be removed for testing.
If melanoma is found, more tests will find the stage of cancer. Melanoma is staged from I to IV. Staging shows if the cancer has spread.
Treatment will depend on the location and stage of the melanoma. One or more treatments may be used, such as:
To help lower the risk of melanoma:
American Academy of Dermatology
Skin Cancer Foundation
Canadian Cancer Society
Canadian Dermatology Association
Kibbi N, Kluger H, et al. Melanoma: clinical presentations. Cancer Treat Res. 2016;167:107-29.
Melanoma treatment—professional version. National Cancer Institute website. Available at: https://www.cancer.gov/types/skin/hp/melanoma-treatment-pdq#section/_1. Accessed September 23, 2021.
Melanoma. EBSCO DynaMed website. Available at: https://www.dynamed.com/condition/melanoma. Accessed September 23, 2021.
Melanoma skin cancer. American Cancer Society website. Available at: https://www.cancer.org/cancer/melanoma-skin-cancer.html. Accessed September 23, 2021.
Last reviewed July 2021 by EBSCO Medical Review Board Mohei Abouzied, MD, FACP Last Updated: 9/23/2021