Garbage's 20th anniversary celebrations were ruined for singer Shirley Manson after she found a lump on her breast and spent weeks on tour fearing she had cancer.

The group had just launched a concert trek in Ireland, when the Stupid Girl singer felt the lump during a morning stretch.

"On the first day of the Version 2.0 Tour, we were due to play in Ireland," she tells "It was all very fantastic and U2 were there and they got us flowers and we hung out with them afterwards. It felt like a real rock 'n’ roll fantasy, you know? And then I went back to my hotel room, woke up in the morning and I was stretching. I ran my hand down my breast, as you do, and I found a lump. I f**king freaked out."

Manson underwent a painful biopsy, explaining, "they couldn’t get the f**king needle in the lump", and finally had the lump removed and taken away for a biopsy as the tour hit the U.S.

"It was a really botched surgery and I was in a lot of pain," she adds. "I had to perform in a sling and I thought I had cancer. You can imagine it’s a sort of heightened hysteria of being away from home and having to deal with something that has serious implications, but as it turned out, everything was fine.

"It was just a lot of madness and so it's only now that I can look back and enjoy the success that we experienced."

And that means Manson has finally accepted she's a bona fide rock star after years spent worrying about her career: "With Version 2.0 (released in 1998), we really stamped our presence. My life changed in that moment. Up until that point I just thought, 'Well, I’m going to be back in Edinburgh (Scotland) before I know it. I’m going to be working back in Miss Selfridge and selling clothes to teenagers', but mercifully, thank God, I didn’t have to go back."

The group will hit the road for a full Version 2.0 Tour later this year (18), performing the hit 1998 album in its entirety.