Emma Todd-Ward thought she was invincible when she lost six and a half stone and got fit again.

Eastern Daily Press: Last year's Race for Life gets under way at Houghton. Picture: Ian BurtLast year's Race for Life gets under way at Houghton. Picture: Ian Burt (Image: Archant © 2013)

But her world fell apart when she was diagnosed with an aggressive form of cancer.

Eastern Daily Press: Thousands took part in last year's event. Picture: Ian BurtThousands took part in last year's event. Picture: Ian Burt (Image: Archant © 2013)

She first realised something was wrong three years ago, when she entered Cancer Research UK's Race for Life and found she was too tired to run.

'After losing weight I'd set myself the challenge of running the Race for Life in 2011,' said Ms Todd-Ward, 42, who lives in King's Lynn and works as a customer assistant at Tesco on Hardwick Road.

'I knew something was wrong because I was suddenly too tired to go to the gym and I had to walk round the Race for Life course.

'I'd had a bit of a cough for six months and a pain in my ribs so I had some blood tests and went for a chest x-ray. That's when I received a phonecall from the hospital saying they thought I had TB.'

Consultants told her they were testing her for lymphoma. Then they broke the news she had it.

'I was in shock at first and my first thought was oh my God, I'm going to die.

'It was a feeling of absolute fear and I remember thinking what am I going to tell the children.'

Ms Todd-Ward, mother of sons Sam, 17, and six-year-old Freddie, began chemotherapy immediately.

'It was frightening because my symptoms were getting worse all the time,' she said.

When that failed to send her 3cms tumour in her left lung into remission, she began a course of radiotherapy.

'I was devastated,' she said. 'You go through all that believing it will all be ok in the end so to be told you're not in remission was awful.

'I had to go to Cambridge every day for radiotherapy treatment and the side effects meant I could only eat liquids because I couldn't swallow.'

By now her hair had fallen out. But the treatment succeeded and she celebrated by entering last year's Race For Life, at Houghton Hall, where she managed to walk the 5km course.

Ms Todd-Ward will be the guest of honour at this year's West Norfolk Race for Life at Houghton Hall, on July 22. She will set 2,000 women off on the 5kms course, when she sounds the starting horn.

Although she can't yet run, she's determined to walk the course and is encouraging women across Norfolk to join her to help raise funds for life-saving research.

'Last year I took part with a team of family and friends and managed to walk all the way,' she said. 'Now I'm planning to do it again and I'm telling everyone I meet to do it.

'Without research I might not be here today so seeing thousands of women uniting for the same cause on Race day is amazing and really quite emotional.'

In Norfolk events take place at Norfolk Showground over the weekend of May 17 and 18 and at Houghton Hall in Kings Lynn at 7pm on Tuesday, July 22.

Rachel Parratt, Cancer Research UK's Kings Lynn Events Manager, said: 'More people in Norfolk are surviving cancer than ever before. But while we're heading in the right direction, too many lives are still being lost to the disease. Sadly, most of us know someone whose life has been touched by cancer and this really brings home how much more work there is to do. Our aim is that one day everyone will beat cancer. The more research we can fund, the sooner that day will come.'

To enter Race for Life's 5k or 10k events in Norfolk click here or call 0845 600 6050.