By Nick Triggle
Health reporter, BBC News, in Edinburgh
Cancer drugs have attracted much controversy
Doctors have called for a thorough and independent review of the ban on NHS patients paying to top up their care.
Anyone in the UK who pays for any form of private treatment can be barred from the normal package of NHS care.
In a debate which split the British Medical Association annual conference, doctors voted for a motion calling for so-called co-payments to be allowed.
They called for a Royal Commission review - but stopped short of demanding an immediate end to the current ban.
The issue has come to a head in recent months as a number of cancer patients have been banned from receiving NHS care after topping up their treatment privately.
It has resulted in some terminally-ill patients being forced to decide whether to pay for health care that would normally be free, or go without drugs that could help extend their lives.
Ministers in England and Scotland have already announced a review of the guidelines following a public outcry, but this is just limited to drugs.
Doctors want it to be carried out independently and also look at a range of other areas of care.
While access to drugs have hogged the headlines in recent months, patients are known to have paid for diagnostic scans to jump waiting lists, while mixing private physio treatment with GP appointments is relatively common practice.
On the eve of this week's doctors' conference, BMA chairman Dr Hamish Meldrum said his "gut instinct" was that it went against the values of the NHS.
But he also said there needed to be a thorough debate and other options considered such as speeding up the way drugs are recommended for use in the NHS before a final decision was made.
In a heated debate, the conference heard from Gordon Matthews, an orthopaedic surgeon whose wife is dying from bowel cancer.
He said the current rules are unfair on patients who are "clinging to their own lives".
"This is not a threat to the NHS. A tax-based system cannot provide unlimited treatment."
He was supported by consultant David Wrede, a member of the centre-right Doctors for Reform group.
He said those against co-payments had an "emotional attachment to some kind of fantasy of what the NHS should be."
And Dr Stephen Austin, of the BMA's consultants committee, said: "This is grossly unfair to these patients at the most vulnerable time of their life.
"This is not what the NHS stands for and goes against the founding principles of the NHS."
But a number of doctors spoke against allowing such top-ups.
Jacky Davis, a consultant radiologist from London, said co-payments would mean the "end of the health service".
"It would overturn a basic principle of the NHS."
Kevin O'Kane, a doctor from London, added it would be a "nail in the NHS coffin" and lead to ever tighter rationing of what is available on the health service.
"We want treatment to be available on the basis of need not ability to pay."
And Mark Porter, also of the BMA's consultants committee, added allowing co-payments would "lever open the NHS" to more charges and drug firms putting pressure on patients.
The conference ended the debate by voting on several motions.
Some 63% said they believed patients should be able to buy private treatment without losing their right to NHS care although 53% accepted that it could create a two-tier NHS.
But they narrowly voted against a motion calling for the government to permit it by 50.2% to 49.8%.
Instead, 71% voted in favour of a Royal Commission to review the issue by summer 2009.