The abnormal growth of skin cells often develops on skin exposed to the sun.
- Asymmetrical – melanomas have two very different halves and are an irregular shape.
- Border – melanomas have a notched or ragged border.
- Colours – melanomas will be a mix of two or more colours.
- Diameter – melanomas are larger than 6mm (1/4 inch) in diameter.
- Enlargement or elevation – a mole that changes size over time is more likely to be a melanoma.
Basal cell carcinoma may appear as:
- A pearly or waxy bump
- A flat, flesh-colored or brown scar-like lesion
Squamous cell carcinoma may appear as:
- A firm, red nodule
- A flat lesion with a scaly, crusted surface
Melanoma signs include:
- A large brownish spot with darker speckles
- A mole that changes in color, size or feel or that bleeds
- A small lesion with an irregular border and portions that appear red, white, blue or blue-black
- Dark lesions on your palms, soles, fingertips or toes, or on mucous membranes lining your mouth, nose, vagina or anus
- UVB is thought to be the main cause of skin cancer
- Artificial sources of light, such as sunlamps and tanning beds
- family history
- pale skin that does not tan easily
- red or blonde hair
- blue eyes
- older age
- a large number of freckles
- an area of skin previously damaged by burning or radiotherapy treatment
- Precancerous skin lesions
- medicines that suppress your immune system (immunosuppressants) – commonly used after organ transplants
- exposure to certain chemicals – such as creosote and arsenic
- a previous diagnosis of skin cancer
- family history
- Remove a sample of suspicious skin for testing (skin biopsy)
- sentinel lymph node biopsy
- physical examination
- blood test
- targeted therapy
- anti-angiogenic drugs