The main types of skin cancer are:
Basal cell carcinoma and squamous cell carcinoma, among other less common skin cancers, are known as non-melanoma or keratinocyte skin cancer. Non-melanoma skin cancer (NMSC) is the most common cancer diagnosed in Australia, with around 400,000 new cases every year.
Basal cell carcinoma
Basal cell carcinoma is the most prevalent form of skin cancer. It accounts for about 70% of non-melanoma skin cancers. It’s also the most frequently occurring skin cancer.
It begins in the skin’s basal cells in the outermost layer of skin (the epidermis). Having one basal cell carcinoma increases the risk of getting another. It’s also possible to have more than one basal cell carcinoma at the same time on different parts of the body. The good news is that most basal cell carcinomas are curable and cause minimal damage when detected and treated early.
FACT: Basal cell carcinoma usually grows slowly. If left untreated it can grow deep into the skin, making treatment more difficult.
Find out more about basal cell carcinoma, including where on the body it most often occurs.
Squamous cell carcinoma
Squamous cell carcinoma is the second most common form of skin cancer. It accounts for around 30% of all skin cancers, if actinic keratoses are excluded from this group. It starts in the squamous cells, in the upper layer of the epidermis.
Squamous cell carcinoma is usually found on areas of the body that get the most sun exposure. This includes the head, neck, hands, forearms, and lower legs. If left unnoticed, squamous cell carcinoma can grow quickly. On a positive note, if found early it is treatable.
FACT: Unlike basal cell carcinoma, which rarely spreads, squamous cell cancer may spread to the lymph nodes and internal organs.
Find out more about squamous cell carcioma, including the signs and how quickly it can spread.
Melanoma also occurs when DNA in the melanocyte cells becomes damaged, most often due to an over exposure of UV radiation. (Sometimes the risk can come from an inherited genetic factor too.) Damage to the cells causes them to reproduce uncontrollably, resulting in melanoma skin cancer.
Melanoma makes up a small proportion of all skin cancer diagnoses (around 3%). However, it is the most serious form of skin cancer. If it’s not found and treated early, it is likely to spread to other parts of the body. Melanoma accounts for 65% of all deaths from skin cancer.
FACT: Only about 25% of melanomas are found in existing moles. About 75% are detected on normal-looking skin without a pre-existing mole.
Find out more about the stages of melanoma and the survival rates.