June 17, 2001

A DRUG made from tree bark is being combined with radiation therapy to cure cancer, experts revealed yesterday. The
'double whammy' has proved 85 per cent effective in laboratory trials.

Last night the treatment was being hailed as a breakthrough in the battle against the disease which kills 133,000
Britons every year.

British experts who made the discovery are already talking of a 'long-term cure' for many common types of cancer
after seeing astonishing results in a laboratory experiment involving human tumours grown in mice.

The dual treatment could be available to patients within five years.

Dr Barbara Pedley of the Cancer Research Campaign said last night: 'We are excited by these results. Our trial shows
that the combination can give a complete cure.'

The tests covered all the major forms of cancer which produce solid tumours, including bowel, breast, liver and

The drug, called combretastatin, works by destroying the developing blood vessels which tumours generate to supply
themselves. Used on its own, however, it leaves a 'rim' of cancerous cells at the edge, allowing the disease to

Radiation therapy completes the attack on the tumour by ensuring all the leftover cells are killed off. Antibodies
with radioactive 'warheads' home in on the disease cells and destroy them.

The advance is part of a new generation

of 'targeted' cancer therapies. Combretastatin, which is derived from the bark of an African bush willow, leaves
normal blood vessels untouched.

The dramatic success story came in a study by the Royal Free Hospital and University College Medical School in
London, and the Gray Laboratory Cancer Research Trust. The results were published in the journal Cancer Research.

The scientists found that human tumours grown in mice disappeared completely in 85 per cent of cases after the
combination of drug treat-ment and radiotherapy.

The animals were still free of the disease almost a year afterwards.

Dr Pedley, head of tumour biology at the CRC's targeting and imaging group at the Royal Free Hospital, said: 'This
combination can produce long-term cures.

'Although we have been mainly looking at colorectal cancer, it works on a very wide range of cancers - all the solid
tumours - which includes breast cancer.'

She said scientists believed the outer tumour cells may rely on the body's normal blood vessels, which is why
combretastatin could not kill them.

Experts now hope to start human trials of the combination therapy as the next stage.

Worldwide tests involving cancer patients are expected to begin next year.

About 200 patients with a variety of different cancers would be recruited to centres in the UK and around the world.

If the trials achieve a similar success rate as those with the mice, they would pave the way for the treatment to
become widely available, possibly within five years.

Experts say it should work against many common forms of cancer.

Dr Lesley Walker, director of cancer information at the Cancer Research Campaign, said: 'This good news confirms
what we have been saying all along - that treatments that directly target cancers and spare normal tissue will be
the therapies of the future.

'As well as improving the effectiveness of treatment, this combination should greatly reduce side-effects for the

More than 220,000 people are diagnosed with cancer each year in Britain.

The latest findings back up early clinical trials involving 34 patients from London who experienced massive tumour
shrinkage after taking combretastatin.

They were carried out by Professor Gordon Rustin, director of medical oncology at Mount Vernon Hospital in

He said yesterday: 'The results from the trial in mice are very exciting because we are actually seeing a cure,
which is very unusual.'

Combretastatin achieved similar results in trials involving 60 patients in the U.S.

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