Types of skin cancer

There are three main types of skin cancer:

1. Basal Cell Carcinoma (BCC)

BCCs are the most common and least worrying type of skin cancer. They arise from cells in the lower part (basal layer) of the upper layer of the skin (epidermis) and tend to grow slowly.

BCCs are most common on the face, head, neck and trunk regions. Nodular BCCs usually appear as a non-healing pimple like lump, which may intermittently bleed, form an ulcer or scab. Superficial BCCs can appear as a red, scaly patch. The less common morphoeic or infliltrating BCCs can be subtle, appearing as a scar-like or shiny plaque on the skin.

BCCs are locally destructive but are generally easily treated in their early stages. If left untreated they can grow and destroy adjoining structures, although they rarely spread throughout the body (metastasize).


Superficial BCC	Nodular BCC

2. Squamous Cell Carcinoma (SCC)

SCCs are the second most common form of skin cancer. They tend to grow much faster than BCCs and most commonly occur on sun-exposed areas such as the face, ears, scalp, lips and backs of the hands. They can occasionally metastasize.

SCCs often appear as a fast-growing pink lump, or wart-like growth, which may have a central 'crater'. They may also break down, crust, bleed and ulcerate. Occasionally they may be tender, or cause a burning or stinging sensation.

People who have had organ transplants, or are immunosuppressed for other reasons, are at higher risk of developing SCCs. Regular skin checks are particularly important in these groups because if an SCC does occur it can behave more aggressively making treatment more difficult.

Bowen's Disease (SCC in situ) is an SCC which has not spread beyond the epidermis (the first layer of skin). They have no risk of spreading to other sites but can develop into an invasive SCC if left untreated. They are usually red, scaly patches and are quite common on lower legs and feet.


SCC	Bowen's Disease

3. Malignant Melanoma (MM)

MMs are less common than BCCs and SCCs, but are much more dangerous. Australia has the world's highest incidence of melanoma and more than 1200 people die from melanoma each year. Like SCCs and BCCs, melanomas can occur on sun-exposed skin, but they also occur on skin that is usually covered, but has been sunburnt in the past. Malignant melanomas may metastasize and cause death.

Most MM start as a new, often dark spot that continues to change. They may also occur in moles which may have been present for years but then change their appearance. Most melanomas are usually asymptomatic, though uncommonly present with itch, or bleeding in the absence of trauma.