Terminally-ill Sir Chris Hoy revealed father was diagnosed with cancer

Sir Chris Hoy's father David was diagnosed with prostate cancer just six weeks before the cycling hero's record-breaking Olympic medal triumph at London 2012.

Britain's greatest-ever Olympian, who has stunned the nation with the revelation that his own prostate cancer is terminal, recalled being told the shock news of his father's diagnosis in his 2012 autobiography.

But unlike Sir Chris, David's cancer was caught early and treated successfully. Sir Chris's grandfather also suffered from prostate cancer, which he too recovered from.

Despite undergoing chemotherapy, Sir Chris, 48, has been told by doctors he has only between two and four years of life left.

In his memoir, Chris Hoy: The Autobiography, the athlete recalled coming home early from a gruelling training camp in Germany, racked with pain from an injury before receiving the news about his father David.

'At 7pm the next evening, my dad called and said he had news for me. And then he told me, perfectly calmly, that he had prostate cancer. It hits you like a sledgehammer.

'Fortunately, after more tests later, the news on my dad was more positive. The doctors seem pretty optimistic that it's treatable. But the relief came later: at the time it was pretty awful for the whole family.'

Sir Chris carried the Union Flag as he led Team GB into the Olympic stadium, then conquered his anxiety and pre-Games injury worries to claim gold in the velodrome in both the keirin and team sprint.

And his proud dad and mum Carol were there to roar him on with every turn of the pedal.

After witnessing Sir Chris's gold medal in the keirin event, David famously unfurled a sign reading 'The Real McHoy'.

And the esctatic dad told reporters: 'I am just so proud of him on every level. I am going to start crying. You bottle everything up and then it all comes out.'

David Hoy, 79, is still currently listed as secretary of his son's company Trackstars Ltd. 

Sir Chris's grandparents on his father's side both died of leukaemia, he revealed some years ago while competing in a charity event for Cancer Research UK. 

The news of his father cancer explained Sir Chris's enthusiasm for that year's Movember moustache growing charity event in which he raised funds for Prostate Cancer UK.

In the UK, about 1 in 8 men will get prostate cancer in their lifetime, according to Prostate Cancer UK.

The disease mainly affects men over 50, and the risk increases with age. The risk is even higher for black men and those with a family history of prostate cancer.

Just before Christmas, Sir Chris's wife Sarra, 40, learned she has a 'very active and aggressive type of multiple sclerosis', which was degenerative and incurable, after experiencing a tingling sensation in her face and tongue and undergoing a scan; on bad days she can struggle to open the front door with her key.

Nevertheless, against all the odds, Hoy has managed to stay positive.

'I'm not trying to pretend that every day is amazing,' he said in an interview with the Sunday Times. 'But I have genuine moments of joy... I'm back to my old self.'

Social media platforms were flooded with tributes and support for Hoy, one of our greatest Olympians, after the news broke on Saturday.

Fellow Olympic cyclist Sir Mark Cavendish called him a 'hero of a human being'. Rugby World Cup winner Matt Dawson said his 'legacy was second to none' and British Winter Olympic champion Amy Williams wrote: 'A pure superhuman who everyone loves.'