NICE advises on which drugs should be bought by the NHS
Some of the UK's top cancer consultants warn that NHS drug "rationing" is forcing patients to remortgage their homes to pay for treatment.
The specialists accuse the government drugs advisory body of "rationing" too severely and call for a "radical change" in the way decisions are made.
Their letter to the Sunday Times also says research success is not being translated into modern treatments.
It follows a decision not to offer some drugs to NHS kidney cancer patients.
Earlier this month, the National Institute of Health and Clinical Excellence (NICE) published its draft guidelines on treatments for patients with advanced kidney cancer.
We have seen distraught patients remortgaging their houses, giving up pensions and selling cars to buy drugs
Letter signed by 26 consultants
It concluded that the drugs - bevacizumab, sorafenib, sunitinib and temsirolimus - did not offer value for money.
But in their letter, the 26 cancer specialists say the decision shows how "poorly" NICE assesses new cancer treatments.
"Its economic formulas are simply not suitable for addressing cost-effectiveness in this area of medicine," they write.
Professor Jonathan Waxman on the cancer drug row
They continue: "It is essential that NICE gets its sums right. We have seen distraught patients remortgaging their houses, giving up pensions and selling cars to buy drugs that are freely available to those using health services in countries of comparable wealth."
The consultants, who include the directors of oncology at Britain's two biggest cancer hospitals, the Royal Marsden in London and Christie Hospital in Manchester, say it is not right the NHS cannot find the money for the drugs.
"We now spend similar amounts to Europe on health generally and cancer care in particular, but less than two thirds of the European average on cancer drugs.
"It just can't be that everybody else around the world is wrong about access to innovative cancer care and the NHS right in rationing it so severely."
There is a finite pot of money for the NHS, which is determined annually by parliament
National Institute of Health and Clinical Excellence
While Britain is a leading contributor to cancer research, this is not translated into "modern treatment for all our patients," they say.
They add: "The time has come for a radical change in how the NHS makes rationing decisions for cancer."
Professor Peter Johnson, from Cancer Research UK, earlier this month also said NICE's decision raised "questions" about whether its system of appraisal was appropriate for all types of drugs.
Andrew Dillon, the NICE chief executive, and Sir Michael Rawlins, NICE's chairman, told the Sunday Times the NHS did not have unlimited funds to provide all available treatments.
"There is a finite pot of money for the NHS, which is determined annually by parliament," they said.
"If one group of patients is provided with cost-ineffective care, other groups - lacking powerful lobbyists - will be denied cost-effective care for miserable conditions like schizophrenia, Crohn's disease or cystic fibrosis."
Dr Evan Harris, a Liberal Democrat MP and former hospital doctor, said rationing was inevitable unless the government increased funding or came up with a fairer way to measure what was cost-effective.
"Attacking NICE is simply shooting the messenger and letting politicians off the hook.
"The government must let NICE get its teeth into vetoing the millions of pounds the NHS spends on wasteful political initiatives - like over-paying private firms to cream off routine NHS cases - and on totally ineffective treatments, like homeopathy.
"That could save the money needed for effective but expensive cancer drugs."
The Department of Health said investment in the NHS had risen from £35bn in 1997 to more than £110bn by 2011.
A spokeswoman said: "We have heard from patients that one of their major concerns is the perceived postcode lottery in access to drugs and that there are too many variations around who gets access to prescribed drugs and that these variations are a lottery depending on where you live.
"The draft NHS constitution will make more transparent and consistent the process for local funding of drugs not appraised by NICE or where NICE has yet to issue guidance."
More than 7,000 people are diagnosed with kidney cancer annually in the UK.
Of these, around 1,700 patients will be diagnosed with advanced kidney cancer.
Although none of the available treatments "cure" cancer that has spread from the initial tumour, they can help extend a patients' life by around five to six months.
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