There are three main types of skin cancer: basal cell carcinoma (BCC), squamous cell carcinoma (SCC) and melanoma.
When detected early, skin cancer is highly treatable. However, if left untreated, skin cancer can spread and become life threatening. This is one of the main reasons why getting to know your skin and regular skin checks are essential.
Basal cell carcinoma (BCC) is the most common cancer in the world. It accounts for around 70% of non-melanoma skin cancers. It usually begins in the lower layer of the skin (epidermis). It can appear anywhere on the body but usually develops on areas which have received high intermittent sun exposure. BCCs should not be left untreated. Very few people die from BCC.
Squamous cell carcinoma (SCC) is the second most common skin cancer. It accounts for about 30% of non-melanoma skin cancers. It usually begins in the upper layer of the epidermis and also tends to arise in areas which have received significant amounts of sun exposure, such as the face, ears, neck, shoulders and back. This type of skin cancer is more dangerous than basal cell carcinoma because it has the ability to spread to other parts of the body. SCC generally grows quickly over months and sometimes weeks.
Melanoma is the most serious form of skin cancer. It can spread very quickly. Once it has penetrated below the surface of the skin it can become life threatening. If detected early, the survival rate is high. This largely dependent on the thickness (depth) of melanoma. If a person has a melanoma of less than 0.75mm thick can expect to have 95% cure rate. If left untreated and larger than 4mm thick, the cure rate is less than 55%. So early detection is key.
Moles primarily form when your skin cells are damaged from exposure to sunlight. Which is why people with fair skin tend who are most susceptible to sunburn are likely to have more moles.
The vast majority of common moles are harmless or benign, but they can in some cases develop into a malignant or melanoma skin cancer.