[OT] 'Re-plumbing' the liver helps beat cancer

[Guest guest]

'Re-plumbing' the liver helps beat cancer

a.. 26 September 2007

b.. NewScientist.com news service

c.. Andy Coghlan

TEMPORARILY diverting blood leaving the liver during chemotherapy could prolong

the lives of people with primary or secondary liver tumours. The hour-long

procedure allows massive doses of chemotherapy drugs to reach the liver and kill

the cancer cells without poisoning the rest of the body.

The regime involves injecting the drug straight into the liver, while using

catheters and balloons to divert the blood leaving it. This blood is then

filtered to remove most of the drug.

" The amount of drug getting to the tumour is hundreds of times more than usual, "

says Taney, president of Delcath Systems, the New York-based company

developing the procedure. Patients are given seven times the normal dose of the

chemotherapy drug melphalan, but because the drug is prevented from spreading

throughout the body its concentration in the liver is far greater than if it had

been injected into the circulation. This increases the chances that tumours will

be killed, even if they are too small to be detected individually.

In an early trial on 13 patients, tumours disappeared or shrank by more than

half in 10 of the patients within five weeks of their being given the new

treatment. They survived for an average of two years. Normally around 90 per

cent of people with inoperable secondary liver tumours die within eight months

of being diagnosed.

The results will be presented next month at the BioPartnering Europe symposium

in London. Delcath Systems has already begun a larger trial in collaboration

with a team led by Pingpank of the US National Cancer Institute in

Bethesda, land.

The procedure uses catheters threaded through blood vessels in the thighs and

neck, one of which delivers the drug into the hepatic artery, which supplies the

liver. Meanwhile, the inferior vena cava, which normally drains the liver (see

Diagram), is blocked by a pair of balloons.

To maintain circulation through the liver, a tube runs through one of these

balloons. Blood leaving the liver is forced into this tube and out of the body

instead of heading for the heart. " We're capturing the effluent, " says Taney.

This blood is then passed through a filter that removes most of the drug, before

being returned to the body through the jugular vein. The drug is infused for

about 30 minutes, and blood leaving the liver is filtered for an hour.

Adam Markham, senior medical adviser to Cancer Research UK, says any

improvements to treatments for cancer that has spread to the liver are welcome.

But he cautions that none of the previous surgical attempts to " isolate " the

liver during chemotherapy by clamping blood vessels have worked as well as was

hoped. He also warns that even though there is no open surgery, the Delcath

procedure might prove too much for very ill patients, and that there would be a

risk that at such high concentrations the drug would damage healthy parts of the

liver.

http://www.newscientist.com/article.ns?id=mg19526233.800 & print=true