Christy Dignam was "devastated" when he was told by doctors he should not perform with Aslan at Dublin's 3Arena.
The Dublin band were due to play at the venue this Saturday, September 17 to celebrate their 40th anniversary with a "lot of special guests joining them on stage", according to guitarist Billy McGuinness.
The band announced today that the show would have to be postponed upon doctors' advice to frontman Christy, who is battling incurable rare blood disease amyloidosis.
Read more: Christy Dignam reveals he was in 'life or death' situation over the summer
"Everything was going so well coming up to our 3Arena show and Christy was doing great. However, he has suffered a set-back with his treatment, and we have now been instructed by his doctors that it is not advisable for Christy to perform this Saturday," the band said today.
Manager for Aslan Denise McCormack told Dublin Live: "It was an extremely emotional day yesterday with lots of tears when we had to tell Christy that the doctors advise was that the 3Arena show wasn’t possible.
"Christy, Joe, Alan and Billy were devastated to hear this news, knowing how many fans they felt they were going to let down but the support and understanding from the Aslan fans and everyone involved in this have been absolutely astounding.
"It means so much to us all and we again thank everyone for the kind well wishes for Christy and also their kindness toward Joe, Alan & Billy."
Fans have been showing their support for Christy and his bandmates since the announcement. One fan commented: "I hope he feels a bit better very soon. You're right guys.. Christy's health is so important."
Another said: "All that's matters is that Christy makes a speedy recovery, sending best wishes." Another Facebook user wrote: "Christy's health comes first above everything. See you guys in the future when he's stronger and up to it."
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