"We were told urgent cancer surgeries would not be cancelled. That was a lie. I'm sick with upset."
David was due to have urgent cancer surgery this morning at St Vincent's University Hospital in Dublin.
Yesterday, he was told it was cancelled. It is the third time this surgery has been cancelled since January.
He's upset but stoic, perhaps because he's been here before. Since 2008, David has been diagnosed three times with cancer.
Even as he waits for his third cancer surgery, a new tumour has appeared on his leg.
David has a type of soft tissue sarcoma, leiomyosarcoma, which is in his abdomen.
He said: "Last July, I was very unwell and ended up in A&E. A radiographer spotted it. Originally, they thought it might be on my pancreas because these tumours are so rare they are often mistaken for other things."
The tumour below his stomach is a source of ongoing pain. "It's the size of a tennis ball," he says.
"I had radiotherapy in October and November not to reduce the tumour, but to loosen it for surgery. I'm in constant discomfort."
"I physically feel it (the tumour), something that's not meant to be there.
"These (cancellations) can't continue because this tumour continues to grow inside me and it'll kill me.
"You make arrangements, get time off work. I had family coming to stay with me.
"My doctors all say I have a good attitude. But when everyone keeps stressing how serious this is, how big an operation this is, you get into the right mental state.
"Then it's cancelled a first time, then a second, and now a third, it's terribly upsetting."
So does he blame nurses for this latest cancellation? No. He doesn't blame anyone.
"There are dozens like me who will have had their cancer surgery cancelled. It's not about taking sides.
"The nurses, the medical teams are the most extraordinary human beings. It's the health system. It's bizarre. Nobody can fix it."