The guitarist has missed a string of live shows in recent years after doctors diagnosed him with the disease, which he thought he had beaten in 2014.

It returned and Campbell underwent chemotherapy and a stem cell transplant in a bid to aggressively attack his cancer.

He tells with The Salt Lake Tribune, "The bad news is this cancer keeps coming back. The good news is the treatment I'm doing largely continues to work, which is a big, big part of the recovery for me; to be able to continue to do what it is that defines who I am.

"I've had three rounds of chemo and last October I did a stem cell transplant. And I kind of naively thought that'd be it, and I was done with it. I guess given the benefit now of my experiences with this, I kinda realise that I'll probably be dealing with it for the rest of my life."

But Campbell admits he's keen to try new drugs and new cancer breakthroughs in a bid to beat the disease once and for all.

He adds, "We're trying a new track now; I'm trying a process called immunotherapy, which is the latest and greatest thinking in how to treat cancer. So, it's part of a clinical trial, and it's early days yet, so I really won't know until the end of the year, I won't really have an idea about the efficacy of this treatment.

"The good news is it allows me to continue to tour, because I just have to do these infusions every three weeks or so. It's a bit of a pain because I have to travel back to Los Angeles. But, as far as side effects, there's absolutely nothing that's of any concern; it's just lowered my thyroid considerably. But if that's the only side effect, I'll certainly take it. It's a lot easier to deal with than doing chemo."

Meanwhile, due to all the time he's missed with his bandmates, Campbell admits he feels like "the new guy in Def Leppard" after 23 years.