Hard cell

But fortunately for him, the Royal Bournemouth Hospital is one of only three centres of excellence in the UK for the diagnosis and treatment of this group of blood and bone marrow disorders, the name of which is usually shortened to MDS.

As a result, Mr Mitchell, of Bournemouth, is one of the few people in the UK to benefit from a new drug that is the first and only one so far proven to boost survival for MDS patients who do not undergo a stem cell transplant.

Among famous MDS sufferers were the late US astronomer Carl Sagan and writer Susan Sontag. Some of the more aggressive forms of the disease can lead to leukaemia.

The RBH was chosen to take part in clinical trials of Vidaza, or azacitidine. The drug works by turning back on inactive genes, allowing normal cell growth rather than the growth of cancer cells. This is what scientists call epigenetic therapy.

Dr Sally Killick, consultant haematologist at the trust, said MDS was more common in older people - the average age at diagnosis is 70, and more cases are seen in Bournemouth because it is a retirement area.

"It's a group of diseases and can affect all blood cells. In some people it might just affect the white cells, or just the platelets," she explained.

"Production of blood cells by the bone marrow is disrupted so fewer make it into the bloodstream, and those that do have a shorter lifespan. The blood cells are also less able to do their normal jobs, hence the term dysplastic.

"Treatment is quite difficult because it's such a mixed bag of diseases, and will depend on the age and fitness of the patient and the stage of the disease.

"No treatment is curative apart from a bone marrow transplant, and patients have to be fit enough to undergo this treatment.

"Vidaza has given us an extra angle to tackle the disease. We're not curing it, we're controlling it. It's the only drug used in MDS ever to have been shown to have a significant impact on patients' overall survival."

Azacitidine is the first of a new type of anti-cancer compounds known as demethylating agents, which Dr Killick believes could work for other cancers. Doctors use an international scoring system to gain some idea of how aggressive MDS is likely to be so they can decide the best way to treat it. One of the original methods was known as the Bournemouth Score because it was devised by three local specialists, Dr David Oscier, Professor Terry Hamblin (since retired from the NHS), and Professor Ghulam Mufti, now at Kings College Hospital in London.

Mr Mitchell was referred to Dr Oscier after a blood test, then on to Dr Killick. He started treatment with Vidaza at the end of May 2006.

"I understand I have an incurable disease but it is just so wonderful to be given each new day," he said. "I don't feel better because I have never felt unwell, but I certainly don't feel any worse."

At the moment, Mr Mitchell, who worked in life assurance before retiring, is having a break from the drug, but he still attends hospital once a fortnight for monitoring.

The married father of three, who also has a grandchild, said: "Dr Killick and her team are absolutely wonderful. You couldn't ask for a better outfit and I have every confidence in them."

FACTFILE

• The bone marrow acts as a factory for blood-forming stem cells, producing white cells, red cells and platelets. MDS develops when something goes wrong in that process, leading to too many defective blood cells and not enough normal ones.

• First described during the 1930s, MDS was not treated as a separate group of disorders until 1976.

• Nearly half of all patients have no symptoms when they are diagnosed, and the syndrome is often picked up as a result of them having a blood test for something else.

• Symptoms can include anaemia, weakness, breathlessness, fatigue, headache, bruising, increased bleeding, rash, fevers, mouth sores and lingering illness.

• In less than a third of patients, MDS goes on to become acute leukaemia. Average age at diagnosis is 70, although children can also have it.