This time last year Bernie Nolan had lost her hair following gruelling bouts of chemotherapy.

Since then she has bared all in Calendar Girls, starred in panto and gone straight into rehearsals for a UK tour of Chicago, which starts in Bradford next week.

Bernie, 51, has come a long way since being diagnosed with breast cancer in 2010. Two of her sisters, Linda and Anne, had fought the disease, and Bernie, who underwent chemotherapy and a mastectomy, was determined not to let it beat her either.

“When it hit me it was a bombshell,” she says. “But I stayed positive and it really helped. I’m one of those annoying people whose glass is half-full, and I decided I was going to attack it rather than let it attack me.

“The doctors said my positive attitude helped me through it. Of course there were dark days, but I wasn’t sick, even with the chemo, and I focused on getting better.

“I can’t stress how important it is for women to check themselves. When I did Calendar Girls I met people touched by cancer, they were so inspiring.”

Prior to her diagnosis, Bernie’s life had been a whirlwind. She’d toured the country in shows including Mum’s The Word and Flashdance, and the Nolans’ triumphant comeback tour. In early 2010 she was runner-up in ITV’s Popstar To Operastar, then came the news that changed her life.

Following Bernie’s cancer ordeal, she “lives for each day”.

“I took the summer off and went to Disneyland with my husband and daughter, then we went on a road trip visiting friends we hadn’t seen for ages. It was one of those things you always say you’ll do but don’t get round to,” she says. “It was lovely having time off. I wanted to make the most of it.

“Any little pain I have now I think, ‘oh God, it’s come back’. Anyone who’s had cancer will tell you that, it’s only natural. But I’m still here. Last Christmas I was bald – look at me now.”

Bernie started performing with her family in Dublin workingmen’s clubs. After moving to Blackpool the act became the Nolan Sisters and, with Bernie as lead vocalist, they became one of the biggest pop acts of the Seventies and early Eighties, with hits including Attention To Me, Don’t Make Waves and floor-filler I’m In The Mood For Dancing.

Gradually, each of the sisters went solo, but in 2009 Bernie, Linda, Maureen and Coleen reunited for the Nolans tour. Gone were the pageboy haircuts and bridesmaid-style dresses – this time the girls worked the stage in stilettoes, surrounded by writhing cowboys and firemen.

“We had an absolute ball,” grins Bernie. “Every night when we went on stage the audience was on their feet, the noise was deafening. I’d be thinking, ‘Are they sure it’s us?’ It was terrific. We’d love to do it again.”

In Chicago, Bernie plays Mama Morton, Cook County Jail’s formidable cell block chief who helps inmates avoid the hangman – at a price. “She’s a hard businesswoman. Those were tough times and a girl had to survive,” says Bernie. “It’s an exciting show, with great roles for women. I love the Bob Fosse choreography, there’s nothing else like it, and it’s a great story. It’s based on real 1920s murder cases but feels like it was written last week.”

Having interviewed Bernie a few times, I’ve always found her friendly, level-headed and funny. For someone who’s been in showbusiness since childhood, she has a refreshingly grounded approach to life.

“It worries me that there are so many kids wanting to be famous,” she says. “My daughter wants to be an actress. She got the LAMDA (London Academy of Music and Drama) grades and wanted to go to stage school, but I said ‘no, you’re going to normal school’. I want her to have stability and a childhood, then she can decide what to do.”

As someone who grafted in clubs from an early age, how does Bernie feel about those who become famous practically overnight, via the TV talent show route?

“If that’s what they want, fine, but this is a difficult business and there’s a lot to learn,” she says. “I remember seeing Myleene Klass in tears when she talked about the abuse she got in the street just because she was in Hear’Say (the pop band comprised of winners of ITV’s Popstars). Nothing prepares you for that. I’d like to think the kids on these shows get the right guidance, but you wonder.

“Now surgeons, God, they’re the people who deserve recognition. My surgeon saved my life. What we celebrities do seems so trivial compared to that.”

* Chicago runs at the Alhambra from February 10 to 18. For tickets, ring (01274) 432000.