He spoke with bravery and eloquence to Joe Duffy this week urging people in Ireland to carry a transplant card which prompted a record-breaking number of people to apply for the cards.
Speaking on RTE's Liveline the father of three explained: "It's an invisible death row. The solution is there, the procedure is there, and the budgets are allocated for the surgery, but the one thing they [medical teams] don't have is organs.
"I want to highlight the situation faced by people who have a life-threatening illness. You're on a transplant list to save your life."
Frank was first struck down with cancer four years ago and he had an operation to remove a tumour, but last January a routine scan showed the disease had returned.
The talented writer now cannot travel further than an hour from his hospital in Scotland, while he continues to write and take care of his three children along with his wife Marie Connolly.
He said: "It's become a critical situation. The problem with a liver tumour is there is only a small window when you can operate. After that the tumour becomes too big and then the cancer spreads.
"So I don't know how long I have left. But it's become urgent. Very urgent," he added.
The 49-year-old Dubliner has a relatively rare blood group B which is shared by just 10pc of the population, and he can only receive a liver from someone of that blood group.
His candid interview with Joe Duffy prompted a record breaking number of people apply for donor cards.
It was the biggest single day in the history of organ donation in Ireland for enquiries from people about donor cards.
"I'm hoping more people will sign up and be donors and talk about organ donation if they are faced with bereavement, and that they do talk about it beforehand," he said.
"It's the public who can save a life. By donating, one woman on Liveline said her son saved five people. That's a modern miracle, but it needs the public to make that miracle happen.
"I know it's a huge decision to make, but allowing your loved one's organs to be used is a huge act of charity."
Meanwhile, Frank is trying to live as normal a life as possible, picking his children up from primary school and doing their homework with them -- while he waits for a phone call to say the hospital have a donor.
"One strange thing is that physically I feel fine. I'm not in any pain, but I'm in a powerless position."
He added: "It's hard to take because I look after myself. I haven't drank for 15 years, and I don't smoke.
"It could be you next. I was living my life perfectly, and suddenly I'm on a ticking clock. The cure is there but you don't have a donor."
Frank stressed that there is always a pressing need for more organ donors, and in his case the issue is "very urgent".
"They're not trying to discover a new drug, these surgeons know exactly what to do, they just need organs. "
The surge in the take-up of donor cards was "very uplifting". He is being backed in his campaign to increase awareness about organ donation by Hollywood star Dougray Scott, who became a good friend of Frank's through Father and Son.
"In raising awareness Frank's not acting for himself; there are many others in a similar situation to him and for me, seeing a friend I love and admire in that situation, I'd do anything to help."
- TEX T 50050 FOR A DONOR CARD
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