Melanoma is a particularly deadly type of skin cancer, but if it is caught early it is mostly curable.
And talking of catching it early – Piers Morgan was alerted to a possible symptom of the cancer by a member of the public.
The Good Morning Britain presenter featured in ‘Serial Killer with Piers Morgan’ documentary back in November when a melanoma expert spotted something worrying.
Gillian Nuttall, founder of Melanoma UK, spotted a blemish on the 52-year-old’s chest just above his open necked shirt, and emailed in to suggest he get it checked out.
She emailed: “Piers, at the risk of sounding like a lunatic, I’m just watching your programme and there’s a blemish on your chest. Have you had it checked?”
Morgan visited a dermatologist who told him the blemish could have turned cancerous – and potentially deadly – had he not had it checked out and removed when he did.
But what is melanoma? It is a type of skin cancer that can spread to other organs in the body, according to the NHS.
A new mole, or changes in an existing one, are the most common signs of the cancer.
However, like Morgan, it could be another mark on the skin, such as a sore, lump or blemish. It could also be indicated by a dark stripe on your emails.
In fact, any change in the way skin looks or feels could be an early warning sign, suggest the American Cancer Society.
Moles and other changes will tend to appear in areas exposed to sunlight, and are rare in places like the buttocks and scalp.
Most cases are caused by ultraviolet (UV) light from the sun, but some are also linked to time spent on sunbeds.
Those more at risk include people with lots of moles or freckles already, pale skin that burns easily, red or blonde hair and a family history of the condition.
The NHS advise that if you notice any changes on your skin you should visit your GP as soon as possible.
An ABCDE moles checklist has also been created to help people tell the difference between a normal mole and a melanoma.
Rates of melanoma skin cancer are on the rise, according to Cancer Research UK. Between 2014 and 2035 there is expected to be a seven per cent increase.