Vicky Phelan will join Ryan to talk about her decision to stop her chemotherapy and looking ahead to Christmas at home with her family.
The CervicalCheck campaigner decided to stop receiving treatment after new tumours were found in her body.
In an Instagram video, the 48-year-old explained that she had enough of putting her body through torture.
“I was horrendously ill for almost two full weeks and I decided that I have had enough of putting my body through torture. At this stage, my treatment is palliative anyway. There is nothing else that can be done medically.”
"And so, I decided that, for me, quality of life is far more important to me now than quantity of life if the extra time that I might get means that I have to go through hell for two-three weeks every month,” she said.
“My focus now is on remaining as stable and as well as I am now for Christmas, which is less than six weeks away....to be able to do the things that are important with my kids like shopping for clothes with my daughter, going to watch my son's soccer matches, [and] going for pizza.
On the day of the release of his new album ‘Flying Into Mystery’, Christy Moore will drop by the RTÉ studios to chat with Ryan fresh from winning his award his Life Time Achievement Award at the RTÉ Radio 1 Folk Awards earlier this week. He will also treat viewers to an exclusive selection of songs from the new record.
Comedian and impressionist Mario Rosenstock will also appear on the show.
He is set to bring a wide array of hilarious characters to The Late Late Show to entertain viewers.
Following the success of last year’s Toy Show Appeal, which raised €6.6m for Irish charities, Ryan will catch up with some of the over 600,000 people whose lives have been changed thanks to the generosity of Toy Show viewers.
And finally, the show will pay tribute to Queen frontman Freddie Mercury, thirty years after he passed away. Ryan will be joined on the show by a Queen Freddie Mercury tribute band for the musical dedication.
Ryan will also have two golden tickets to give away to The Late Late Toy Show.
The Late Late Show, RTÉ One, Friday, November 19th at 9:35 pm.