In the space of one week last June, mother-of-three Jayne Lawton went from believing she was too young to get breast cancer — to fearing she would die before her children grew up.

Mrs Lawton, now 38, and of Wheat-fields in Didcot, was stretching her muscles after a shower when she not-iced a lump at the top of her left breast.

Curious, but not concerned, she told her husband Jim and he told her to make a doctor's appointment.

The next day she visited her GP who told her that if it hadn't gone down in a week, she should come back.

But Mrs Lawton didn't want to wait, and she made a private hospital app-ointment.

A week after finding the lump it was tested, but the results were unclear.

Another week later she had a mammogram and an ultrasound which revealed a second lump.

And just four weeks after first going to the doctor, a consultant sat her down and told her she had an aggressive form of breast cancer.

Mrs Lawton said: "I remember Jim sitting beside me, shaking, as we listened to the consultant telling me I would need an operation, then chemo-therapy and radiotherapy. He told me the younger you are, the more aggressive cancer can be."

More than 45,000 women are diagnosed with breast cancer each year — more than 120 new cases each day.

Less than four per cent of breast cancer victims are aged between 35 and 39, but Cancer Research UK has urged women of all ages to check themselves for the disease.

Mrs Lawton said: "I remember thinking ‘I can't have cancer, I'm only 37’."

The Lawton's decided not to tell their three children, Jasmine, then eight, Elias, six and Sebastian, two, about the cancer, but to try and carry on as normally as possible.

Mrs Lawton said: "Looking after them helped, and I carried on going to work (as a part-time practice manager for a solicitor), but there were lots of tears in the coming weeks.

"I remember one day sitting with Seb-astian playing with a tea set and it suddenly struck me just what could happen.

“I asked myself if I was going to die and whether I would see the children grow up. Thankfully, Jim was so positive and the doctors were very encouraging, giving me 90 per cent odds of still being alive in 10 years."

Mrs Lawton underwent two lumpectomies (surgery to remove the lumps) and chemotherapy. The last chemo session was a week before Christmas and radiotherapy started in January 2008.

In March, keen runner Mrs Lawton took part in the Reading Half Mara-thon. She said: "I'd used the goal of taking part to help get me through the months of treatment and it felt amazing to complete the course."

She must now take the cancer drug Tamoxifen for the next five years. She added: "Since getting the all-clear my fear of dying has gradually waned, mainly thanks to Jim's support.

"Because of my age I didn't think I was at risk and although I used to check my breasts, I didn't do it that regularly. Now I know that it probably saved my life."