When former footballer Geoff Thomas was diagnosed with leukaemia, he was determined to beat the disease and to raise as much money as possible for cancer research and treatment - so with the determination that had served him well in his sporting career, he set himself a extraordinary challenge, writes Sally Oldaker.

As a professional footballer, Geoff Thomas achieved heights that some players can only dream of - as well as playing for seven clubs around the country, he won nine England caps and led Crystal Palace in the 1990 FA Cup Final against the mighty Manchester United.

But perhaps the proudest moment in Geoff's life was when he rode down the Champs Elysees in Paris on July 21, having completed the exhausting Tour de France route just months after going into remission from chronic myeloid leukaemia.

Geoff was diagnosed with the disease in July 2003, after visiting the doctor with stomach pain and breathlessness. "I'd been ignoring it for months, but my wife Julie finally made me go and get checked out," he admits. "They did some blood tests and told me to expect the results in six weeks - but about three hours later the doctor phoned me...so I knew it was bad news."

Happily the cancer had been detected in the earliest of its three stages: chronic, accelerated and blastic. Treatment began the very next day, first at the Alexandra Hospital in Redditch and then the QE in Birmingham, where Geoff underwent dialysis to clean his blood ahead of a course of chemotherapy.

"It all happened so fast that I hadn't had time to sit down and consider the situation," he recalls. "The specialist at the QE, (Professor) Charlie Craddock, was excellent - he explained it all in black and white. My only real chance of living for longer than about three years was to have a bone marrow transplant, and the best match would be my sister."

His only sister, Kay Hill, immediately agreed to be tested, both siblings knowing that there was just a 20 per cent chance of a match - it would be extremely difficult to find one outside the immediate family. The alternative, treatment with drugs, would only prolong Geoff's life rather than curing the cancer.

Geoff, who lives in Barnt Green, responded to his situation by spending as much time as possible with Julie and their two daughters, now 12 and nine. He and Julie had been running a successful clothing business since his retirement from football in 2002, and this went on hold as news of Geoff's condition became known.

Kay's bone marrow proved to be a match, and after an intensive course of chemotherapy and radiotherapy, the transplant took place in January 2004; a tough process for both of them. "I'd started to look like a typical cancer patient," Geoff says ruefully. "The transplant was successful, but it takes time for the body to repair itself, and you are still very vulnerable to viruses for some time."

In January 2005, Geoff was told that his cancer was in remission; that is, there was no longer any evidence of leukaemia in his body. Long before he received the wonderful news, he had decided to become involved in fundraising for leukaemia charities, to give something back to the people and places that had saved his life.

"Charlie Craddock had mentioned that the Birmingham charity, Cure Leukaemia, was hoping to build a specialist research centre and improved facilities for leukaemia patients at the QE - I thought that since people know me, I'd be able to raise a decent amount for them, and also for the national charity, Leukaemia Research."

The idea for the Tour de France came about when, a month after his diagnosis, Geoff was given a copy of Lance Armstrong's autobiography, detailing the six-times Tour winner's own battle with cancer. "I found it very inspirational and just what I needed," he remembers. He was later interviewed by a journalist (and Crystal Palace fan), who promised to help think of fundraising ideas.

"At Christmas 2004, he suggested following in Lance's footsteps and cycling the route of the Tour de France," says Geoff. "I thought: just imagine if I could get fit enough to do that and raise a lot of money! I got very excited about it, and once companies agreed to sponsor the trip, there was no turning back!"

As soon as he was in remission, Geoff started his training programme, cycling on the Lickey Hills and in the Cotswolds to familiarise himself with mountainous terrain. Knowing that the 3,548-km ride would see him cycling an average of 160km per day for 21 days, he had to prepare himself mentally as well as physically for the challenge.

Did his years of football (at Rochdale, Nottingham Forest and Wolves, to name a few of his other clubs) help him to prepare? "Definitely. The fact that I had a base level of fitness - and knew all about fighting for what I wanted - helped me to beat cancer as well as getting ready for the ride. As a sportsperson you do learn to set a series of targets for yourself."

Apart from owning a racing bike as a youngster and the occasional ride as a break from football training, Geoff had not done a lot of cycling before, but enjoyed watching the Tour de France on television. "I didn't understand how much technical stuff and team work went into it - I do now!"

His own team of five people, on bikes supplied by Bianchi, also had support from Land Rover vehicles packed with equipment, a physio from Crystal Palace, a nutritionist, cooks and a mechanic (who also rode the route) as well as sponsorship from Sport in Science energy drinks. The team was joined by none other than Alistair Campbell, the former Communications Director for Tony Blair, on the penultimate stage of the challenge.

"The moment when we approached the finish line was amazing," Geoff enthuses. "There were about 50 people waiting to welcome us, including family and friends, Charlie Craddock, a team from Cure Leukaemia, and even some Midlanders who were visiting Paris and heard about the ride!"

"The personal achievement ranks above everything else I've done," he continues, quietly but proudly. "To go from thinking you've got three years to live, to riding a bike for over 2,000 miles...well, people thought it was impossible. It proved to me that I still have drive and determination, and of course it raised a massive amount of awareness for the cause."

£140,000 has been raised so far, with the figure expected to reach £200,000 (the target sum) with a fundraising dinner in October. The new leukaemia centre at the QE is scheduled to open in the new year, and fundraising efforts will continue in order to provide the best equipment and staff. "Some of the top people in cancer research and treatment are in the Midlands, and you don't realise until you become involved yourself."

Geoff won't be declared officially clear of cancer for another four years, and there is a 20 per cent chance the disease could come back before that time. "The odds are 80 per cent in my favour," he says philosophically. "It's always going to be in the back of my mind - but I just have to get on with my life!"

To find out how the fundraising is going, and to read Geoff's Tour de France diary, visit www.geoff-thomas.com.

Leukaemia Research 020 7269 9004 www.lrf.org.uk

Cure Leukaemia 0121 452 5081