Following a difficult period of health concerns, Vivian Campbell has emerged happy, engaged and ever vigilant. He says in the aftermath of a Hodgkin's lymphoma relapse, he'll be keeping a close eye in case the cancer returns once more.

"Well, I seem to be in a good spot at the moment," Campbell recently told Eddie Trunk. "You can never be too certain with these things, because they can come creeping back."

Campbell, who will be part of new albums by Def Leppard and Last in Line in 2015, thought he had beat his cancer. But he was forced into two rounds of chemo and a stem-cell transplant after learning the lymphoma had returned in 2013.

The new year brings better news, however. A initial post-transplant scan "came back really, really good. There's no sign of the tumors," Campbell confirmed. "So, I'm hopeful that we're on the right path. I mean, that's certainly the way I've been thinking. I'm not letting it concern me at all. But continuing for the next few years, I'll be doing more scans and follow-ups and stuff, just to make sure, but I'm certainly feeling healthy, you know?"

Campbell was first diagnosed in the spring of 2013, as Def Leppard continued a residency in Las Vegas. "As soon as we were done with that, I started six months of chemo," he recalled. "And I just kind of naturally assumed you do the chemo, you do a scan at the end of the chemo and it shows that you're good, and that's it. But apparently not. It was, like, 90-something percent gone, and it was what they couldn't see on the scan that came creeping back. And it came back so fast."

Meanwhile, Campbell said he's been humbled by the outreach from fans who have gone through similar situations. "You put this kind of stuff out there, and I personally was amazed by how rampant it is -- how many people have been affected by it to some degree, or people that are close to them in their family," he said. "I've had a lot of advice, but to be honest, I'm just pigheaded and Irish, and I just do my own thing. The main thing for me was to continue working, and in fact, to continue my life unabated, and to not let it compromise me as much as possible. And I think that's been a big part of my mental recovery on this."

Trixter guitarist Steve Brown subbed for Campbell with Def Leppard while his treatment continued. Last in Line were scheduled to finish their new project in the coming weeks; Def Leppard's album may be out as soon as spring.

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