Former Wales and Celtic footballer John Hartson has admitted he ignored signs of testicular cancer two years ago.
Speaking to The Sun, the 34-year-old said he did not go to a doctor after finding a lump and only sought medical help after blinding headaches.
Hartson, from Swansea, was released home from hospital on Tuesday after undergoing treatment for cancer.
He is having chemotherapy after being diagnosed with testicular cancer which spread to his lungs and brain.
The father-of-three, who also played for Arsenal and West Ham, urged men to get checked by doctors if they notice anything abnormal on their bodies or under their skin.
He told the newspaper that ignoring the growing lump was a "bloke thing".
"There was a lump in my testicles which I noticed a good while back. I just didn't do anything about it," he said.
"It was worrying, I'd be lying if I said it wasn't."
Hartson also revealed he had told his girlfriend Sarah McManus about the lump but informed her she should not worry.
"I should have gone to the doctor right away and things might be so different now," he said.
"Don't wait, because the cancer spreads and all of a sudden you're in big trouble."
Aaron Ramsey and Robert Earnshaw in Wales shirts supporting cancer charity
Ms McManus told the paper: "Everyone is thrilled that John has been allowed home. But the last few weeks have been horrendous."
The Wales football team will wear a specially-designed patch supporting a cancer charity on Wednesday night and their shirts for the friendly against Montenegro will be auctioned on eBay following the game, the Football Association of Wales (FAW) confirmed.
An FAW official said: "We will have patches on the players' shirts for the match supporting a charity that works in aid of a cancer charity, checkemlads.com, specifically for male cancer problems.
"The players are concerned about John's situation. Apart from the patches on their shirts, they will also wear T-shirts during the warm-up for the match with John's name on them.
"Afterwards we will get all their shirts back and then auction them for charity."
Hartson was initially treated at Swansea's Morriston Hospital in south Wales before he was transferred to a cancer ward at Singleton Hospital in the city last week.
He was discharged from hospital on Tuesday.
The hospital said he would continue with chemotherapy as an outpatient.
'Signs and symptoms'
His family has also issued a statement thanking all the staff at the two hospitals for "their support in getting John to this stage in his treatment".
In a statement on the FAW website, Ms McManus said: "Along with our chosen charity www.checkemlads.com who are forming a specific John Hartson Foundation, I would stress the importance of visiting the website, so that men can make themselves aware of how to check themselves and know the signs and symptoms of testicular cancer."
Hartson retired from football in February last year and had been working as a television pundit.