Bravely, John's wife Nadia and daughter Daniella spoke to the Sun newspaper about John's terrible ordeal to raise awareness about skin cancer and the importance of getting the right treatment.
Having nagged her father to make the original appointment with his GP in Tunbridge Wells, Daniella said John was told the mole on his chest was nothing to worry about.
The GP told him she had no concerns but took a picture to show colleagues, assuring him if they thought otherwise they would phone him. But the call never came and so John, a self-employed surveyor, carried on with life as usual.
Around seven months later, he noticed the mole had changed again - it was darker and had grown in size. He went back to the doctors and this time he was seen by a different GP who described it as looking like a 'little blueberry'. They referred him to see a dermatologist under a two-week cancer referral.
It took almost a month before John received a letter with an appointment but on the day he was due to go to hospital he received a call to say they were overbooked.
Nadia Heywood said that every week, the mole was getting bigger and more painful.
A couple of weeks later, the mole became infected and John went to A&E. Doctors sent him home with antibiotics.
The following week, John went to his rescheduled appointment where a nurse took more pictures and told him they’d be in touch the next day - again he heard nothing. Things took a turn for the worse when a fortnight later, John started feeling seriously unwell. Nadia called for an ambulance but it took seven hours for him to be seen - and he was subsequently diagnosed with life-threatening sepsis.
It was only after being admitted to hospital that doctors carried out more tests and confirmed that the mole was in fact cancer.
Nadia said: “By this point, it was quite round and the size of an egg, with a hole in the middle. He was in a lot of pain.”
Eventually, John underwent seven-hour surgery to remove the tumour which by now had spread from his chest under his arm. Despite undergoing immunotherapy and chemotherapy, the cancer returned and doctors told the family there was nothing more they could do.
John's family decided to speak to the press to hopefully prevent anyone else going through a similar tragedy.
What is melanoma and how to recognise it
The most common sign is a new mole or a change in an existing mole.
In most cases, melanomas have an irregular shape and are more than one colour.
The mole may also be larger than normal and can sometimes be itchy or bleed.
Look out for a mole which changes progressively in shape, size and/or colour.
The ABCDE checklist to tell the difference between a normal mole and a melanoma:
- Asymmetrical – melanomas have 2 very different halves and are an irregular shape
- Border – melanomas have a notched or ragged border
- Colours – melanomas will be a mix of 2 or more colours
- Diameter – most 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
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