Different Types of Skin Cancer1,2,3There are three types of skin cancer in order of gravity: melanoma, squamous cell carcinoma, and basal cell carcinoma. A complete description of each is provided below. Have a dermatologist thoroughly check your body once a year for skin cancer, and report suspicious moles immediately.
Melanoma
- Arise from melanocytes (pigmented cells in the skin)
- Can develop in or around lesions already on the skin or in healthy looking skin
- Some types caused by UV radiation exposure although may also arise in unexposed areas of the skin
- Easily curable if caught early before metastasis, however deadly if caught after metastasis
The characteristic symptoms of malignant melonoma are defined by ABCD (Asymmetry, Borders, Color, Diameter) criteria:
ABCD Criteria for Malignant Melanoma |
|
| A = Asymetry | Halves do not match |
| B = Borders | Edges are irregular or vague |
| C = Color | Two or more colors are present |
| D = Diameter | Larger than one quarter inch |
Squamous Cell Carcinoma
- Arise from keratinocytes (skin cells)
- Primarily caused by UV radiation (even at levels well below those that cause sunburn)
- Typically slow growing although certain types may grow quickly
- Most commonly seen at sun exposed sites (ears and lower lip) however can be found elsewhere (genitals)
- Much higher risk of metastasis and death than basal cell carcinomas however less so than malignant melanomas
Basal Cell Carcinoma
- Arise from Basal Cells (a different type of skin cell)
- The most common type of skin cancer in humans and the least deadly
- Appear on sun-exposed skin, slow growing, rarely metastasize
- Flat, firm, pale area that is raised, translucent, pink/red, shiny/waxy and may bleed after minor injury
References1. Tan WW. Malignant Melanoma. http://emedicine.medscape.com/article/280245-overview: Medscape Reference; 2012.2. Khalyl-Mawad J. Pathology of Squamous Cell Carcinoma and Bowen Disease. http://emedicine.medscape.com/article/1960631-overview#a30: Medscape Reference; 2012.3. Bader RS. Basal Cell Carcinoma. http://emedicine.medscape.com/article/276624-overview: Medscape Reference; 2012.