Doru Paul, MD, is triple board-certified in medical oncology, hematology, and internal medicine. He is an associate professor of clinical medicine at Weill Cornell Medical College and attending physician in the Department of Hematology Oncology at the New York Presbyterian Weill Cornell Medical Center.
Skin cancer is the most common type of cancer in the United States, accounting to 3.3 million people diagnosed with this condition. There are three main types: squamous cell carcinoma, basal cell carcinoma, and melanomas, as well as some less common cancers.
Symptoms may include a sore that doesn't heal, a new spot on the skin, or a mole that has undergone recent changes.
When doctors suspect skin cancer during an exam, a biopsy is needed to make the diagnosis. Treatment options depend on the type and stage, with surgery to remove cancer being the most common approach. With melanomas and advanced squamous cell carcinomas, other treatments such as immunotherapy, chemotherapy, or radiation may be needed. However, there are many simple things you can do to lower your risk.
The various types of skin cancer, in general, look different. The mnemonic device ABCDE (and F) can be employed specifically for melanoma to help recognize when a skin change may be suspicious for melanoma:A: Asymmetry
E: Elevation or evolution
F: "Funny looking"
Itchiness can have many benign causes, but in some cases it can be a symptom of skin cancer. See your doctor if you have a persistently itchy mole or sore that just doesn't seem to be healing.
The most common forms of skin cancer, squamous cell and basal cell cancers, in general, are not fatal as they're unlikely to spread to other areas of the body. Melanoma, the rarest form, is the most aggressive and can be deadly, however, melanoma can be curable when detected early. The estimated 5-year survival rate for those diagnosed with an early stage of melanoma is 99%.
In the early stages, basal cell and squamous cell carcinomas are often dismissed as bug bites or other minor skin irritations—they may feel itchy, bleed, or ooze, but are unlikely to hurt. As skin cancers get larger, they may feel painful or sore. In cases of melanoma, a mole that has been on your body for a long time may begin to hurt or itch.
A skin cancer originating in the innermost layer of the epidermis. Lesions are described as pearly raised bumps (papules) that often appear on areas of the skin usually exposed to sunlight. Basal cell carcinoma is the most common of the non-melanoma skin cancers, and is very treatable. Skin damage from UV light (tanning beds and sun exposure) is the primary cause.
A tumor or growth that is not cancerous (malignant). In some situations and conditions, cells may multiply abnormally but won't spread or invade other tissues or parts of the body.
A treatment that uses drugs to kill any cells that are rapidly dividing in the body. By definition, this includes cancer cells, but chemotherapy may also kill healthy cells that divide quickly, which is why side effects include low blood cell counts and hair loss. Chemotherapy may be used in skin cancer when the cancer has metastasized (spread to other tissues and organs).
A procedure that involves freezing skin cancer cells. Cryotherapy is used to treat small skin cancers, especially when there are a large number of precancerous/cancerous lesions. Cryosurgery procedures may need to be repeated to treat persistent lesions, and it may leave a scar.
A tumor or growth that is cancerous (not benign). With malignant cancers, abnormal cells mutate or divide rapidly and may spread or invade other tissues or parts of the body.
A form of skin cancer that originates in a melanocyte, a cell that gives skin its pigment (melanin). Melanomas may appear as a new spot on the skin or arise from an existing mole. While considered to be the most aggressive form of skin cancer due to its ability to quickly spread, melanoma is considered very treatable when detected early.
A condition when a cancerous growth or tumor spreads from a primary site where the cancer originated to a secondary site in the body. For example, melanoma and other skin cancers may sometimes metastasize to the lymph nodes or other tissues or organs.
A procedure that uses high-energy X-rays to kill cancer cells. Radiation therapy may be necessary in the treatment of melanoma when the cancer has spread to lymph nodes.
The second most common type of non-melanoma skin cancers, squamous cell carcinoma originates in the keratinocytes, cells in the thickest layer of the epidermis. It is caused by UVB rays that penetrate and damage skin often exposed to sunlight without protection, most often the scalp, lip, back of the hand, and the upper tip of the ear. While it is treatable, prevention is especially important.
American Cancer Society. Key Statistics for Basal and Squamous Cell Skin Cancers. Updated January 8, 2020.
Apalla Z, Nashan D, Weller RB, Castellsagué X. Skin Cancer: Epidemiology, Disease Burden, Pathophysiology, Diagnosis, and Therapeutic Approaches. Dermatol Ther (Heidelb). 2017;7(Suppl 1):5–19. doi:10.1007/s13555-016-0165-y
Seiverling EV, Ahrns HT, Bacik LC, Usatine R. Biopsies for skin cancer detection: Dispelling the myths. J Fam Pract. 2018;67(5):270-274.
Skin Cancer Foundation. Melanoma. Updated May 2020.
Berking C, Hauschild A, Kölbl O, Mast G, Gutzmer R. Basal cell carcinoma-treatments for the commonest skin cancer. Dtsch Arztebl Int. 2014;111(22):389-95.
Baskar R, Lee KA, Yeo R, Yeoh KW. Cancer and radiation therapy: current advances and future directions. Int J Med Sci. 2012;9(3):193–199. doi:10.7150/ijms.3635.
Prohaska J, Badri T. Cryotherapy. In: StatPearls. Treasure Island (FL): StatPearls Publishing; Updated August 23, 2020.
American Cancer Society. What are basal and squamous cell cancers? Updated July 26, 2019.
Centers for Disease Control. What are the symptoms of skin cancer?. Updated April 9, 2020.