Skin Cancer Basics – Part One
Skin canceroccurs when skin cells start growing abnormally, causing cancerous growths.
Most skin cancers develop on the visible outer layer of the skin (the epidermis), particularly in sun-exposed areas (face, head, hands, arms, and legs). They are usually easy to detect by examining the skin, which increases the chances of early treatment and survival.
What are the different types of skin cancer?
There are different types of skin cancer, each named for the type of skin cell from which they originate. The majority of skin cancers fall into one of the following categories:
- Basal Cell Carcinoma (also called BCC) comes from the basal cells in lowest part of the epidermis. 80-85% of skin cancers are basal cell carcinomas.
- Squamous Cell Carcinoma (also called SCC) comes from the skin cells (keratinocytes) that make up the top layers of the skin. About 10% of skin cancers are SCC.
- Melanoma comes from skin cells called melanocytes, which create pigment called melanin that gives skin its color. 5% of all skin cancers are melanoma. Although less common, melanomas are a very dangerous type of skin cancer and are the leading cause of death from skin disease.
Basal cell and squamous cell carcinoma are sometimes referred to as "non-melanoma skin cancer" to distinguish them from melanoma.
There are a variety of less common types of skin cancers, including cutaneous T-Cell Lymphoma (CTCL) and Merkel cell carcinoma.
Skin cancer is considered low risk when the affected cells remain clustered in a single group. It is considered high risk when the cells have invaded surrounding tissues. High risk forms of cancer require more aggressive treatments.
Almost all skin cancers start as a small, low-risk lesions, but can grow and become high-risk lesions if left untreated. Melanoma is the most alarming type because it has a higher risk of invading surrounding tissues or spreading to other parts of the body (metastasis) before being detected. Squamous cell and basal cell skin cancer are more likely to be detected and treated effectively before they become malignant.
Reviewed and approved by: Dr. Keith D. Wright