Had Jane Tomlinson been granted a long and healthy life, it is unlikely that she would have become known beyond her home town of Rothwell, near Leeds. But she became extraordinary — and famous — when, in 2002, she ran the London Marathon while suffering from terminal cancer.

Despite numerous operations and hospital stays she went on to complete a succession of increasingly gruelling physical challenges, including, in August 2003, the Ironman, a triathlon comprising a 2.4-mile swim in open water, an 112-mile bike ride and a full marathon. She wanted, she said, to "send a message to people that there are lots of things that happen in life that you have no control over, and things you can do to keep control".

Her last expedition - followed closely by thousands in the media and via the blog written by her husband, Mike - was a 4,200-mile journey in July and August last year from the Golden Gate Bridge in San Francisco, through the Nevada and Utah deserts and the Rocky Mountains in Colorado, to New York.

It was an immense challenge, and she was already in pain from her illness. Many feared that she would not complete it. But she did, and in doing so she brought the amount she had raised for charity to more than £1.2 million, and was praised as a source of inspiration to other cancer sufferers worldwide.

She was born Jane Goward in Wakefield in 1964. Her family lived in Liverpool before emigrating to Australia. She met her husband in Leeds in her early twenties and settled there. She was a 26-year-old mother of two when she was found to have breast cancer. After undergoing a mastectomy she began a diploma in radiography. “I had a sense that I could do that job because I knew what it meant to be a patient,” she said.

When the cancer returned three years later it was treated successfully with chemotherapy, radiotherapy and an anticancer drug, but in 2000, after the birth of her third child, it was found to have returned and spread to her bones. She was told that it was likely that she would die within 12 months.

"Everyone wants to wrap you in cotton wool," she said later, "and the running was a way of showing I could still do something positive . . . . It also helped to relieve all the anger, the sense that this was so unfair and why was it happening to me?" Her first race was the 5km Race for Life in May 2001. In December that year she doubled that distance in the Leeds Abbey Dash.

At 5ft 2in (1.6m) and seven stone (44.5kg), and with no previous athletic pedigree, Tomlinson perhaps seemed poorly equipped to take on great physical challenges, even without having had years of cancer therapy; and her brief remission ended in January 2002. Yet the pace of her achievements began to outstrip the progress of the disease. She ran her first half marathon in York, and in April 2002 completed the London Marathon in a respectable 4 hours, 53 minutes. In July she presented the Jubilee baton to the Queen at Temple Newsam in Leeds and in August became the first terminally ill athlete to compete in the London Triathlon, finishing with the first half of the field. In October that year she completed the Great North Run.

In 2003, after once again completing the York Half Marathon, she undertook a trip by tandem from John O’Groats to Land’s End with her brother, Luke. She managed to complete the journey in 21 days, averaging 50 miles a day despite two enforced stops for chemotherapy. The ride raised £96,000.

The following year she and her brother went on another, 1,900-mile, cycling trip, riding from St Peter’s Square in Rome to Leeds, via the Mont Ventoux in France and the Alps. Tomlinson endured exhaustion and considerable pain, and when she returned she was greeted by the mayor and a thousand-strong crowd. In 2005 she ran the New York marathon, in five hours 15 minutes.

After announcing this year that she had completed her last challege, Tomlinson organised a 10-kilometre event, Run for All, for about 10,000 runners, which took place in Leeds in June.

Tomlinson talked about her illness straightforwardy and with humour. In 2005 she and her husband published The Luxury of Time, in which they contributed alternate chapters and showed a complete lack of self-pity.Tomlinson received numerous awards, including the BBC Sports Personality of the Year award in 2002, and a Pride of Britain Award in 2005.

her fund-raising challenges were undertaken, she said, in the hope that "research will lead to more than just a few years being added to people’s lives — so that people are able to live without death always looking over their shoulder". The money she raised — now £1.75m — went to, among many other charities, Macmillan Cancer Relief, Sparks (Sport Aiding Medical Research for Kids) and Damon Runyon Cancer Research.

Tomlinson was appointed MBE in 2003 and CBE in June this year.

She is survived by her husband and children.

Jane Tomlinson, CBE, radiographer and charity fundraiser, was born on February 21, 1964. She died on September 3, 2007, aged 43