Skin cancer is a malignant tumor develops from the tissue of the skin. There are several types of skin cancer, named depending on the group of cells affected: squamous or non-melanomas and melanomas.
Melanoma is a cancer that forms in a group of cells called melanocytes. They produce melanin, and are found in the skin, eyes, inner ear and the meninges. Unlike other type of skin cancer, melanoma tends to grow quickly, and can be fatal. In fact, it is the most dangerous form of skin cancer. Melanoma is responsible for nearly 75% of deaths from skin cancer.
Carcinomas are composed of two main types of skin cancers: basal cell carcinoma and squamous cell carcinoma. They are the two most common forms of non-melanoma, representing more than 80% of skin cancers. Basal cell carcinoma is the most common. Squamous cell carcinomas are rare; they are often the result of metastatic cancer cells that have spread beyond the original tumor.
In general, the evolution of basal cell carcinoma and squamous cell carcinoma is slow and rarely fatal. They occur most often in people aged over 50 years.
Other non-melanomas – although rare, the following are other types of non-melanoma:
- merkel cell carcinoma
- sebaceous glands Carcinoma