When Michelle Betts found a lump on her breast in August 2012, it led to a double cancer shock.

The mother-of-one was given the devastating news that she had breast cancer, but was also told that there was a primary site of disease that doctors have never been able to find.

The Norwich businesswoman, who refused to be beaten by the rare cancer, received the news two weeks ago that she had the all clear after a lengthy spell of treatment.

The 44-year-old is now urging other women to join the fight against cancer by signing up to Norfolk's Race for Life events to raise funds for Cancer Research UK.

Mrs Betts, of Norman Drive, Old Catton, is set to be the guest of honour and will sound the starter horn at the 5k event at the Norfolk Showground in Costessey on Saturday May 17.

The former patient, whose parents have both been treated for cancer, was diagnosed with the disease in September 2012 and had an operation at the Norfolk and Norwich University Hospital two months later to remove the tumour in her breast and 25 lymph nodes.

Mrs Betts, who manages the family-run Able Care Agency in Norwich, underwent six months of intensive chemotherapy after medics were unable to find the primary site of cancer. She added that she did not feel unwell at the time of her diagnosis.

'I had every type of scan and they could not find it. We are guessing that it was so small that the chemotherapy has hopefully destroyed it. It is more annoying for my oncologist because they wanted an end to it,' she said.

Her cancer was of an aggressive type and was 'triple negative', meaning it would not respond to commonly used breast cancer treatments such as hormone therapy or Herceptin.

However, she stayed positive and continued to work throughout her treatment.

'Because my mother-in-law died of breast cancer in 1985, I have always been quite vigilant and have checked myself. In those days people did not mention cancer and now it is talked about much more it is not something to be ashamed of. It is not a death sentence anymore. I wanted to be in control and I did not want to let it control me,' she said.

Mrs Betts will be taking part in her third Race for Life on May 17 and will be running with her mother, Babs Colbourne, of Old Catton, who has had treatment for bowel cancer.