As happens in the media, the excitement generated last week by the headline that cancer could be detected in the blood was overdone. The results announced in Science magazine are a long way short of meaning that the earliest signs of cancer can be detected in people with no symptoms: the 70% success rate in finding DNA from 16 cancerous genes was in people already diagnosed with serious cancers. False hopes may have been raised.
But behind the headline, there is little doubt that a revolution in diagnostics is happening. Till now, the slow process of culturing infectious agents to identify them has not changed much since the days of Louis Pasteur. It is becoming increasingly possible to identify the precise virus, bacterium, drug-resistant strain, antibody or telltale molecule that defines exactly what is wrong with somebody, quickly and without invasive procedures or lengthy cultures in distant labs. Yet Britain is lagging behind comparable countries in joining that revolution.
Proteins, fatty acids or DNA sequences, even if present in minuscule concentrations, can now be picked out by new techniques that combine biochemistry and electronics in ever more ingenious ways. Clever algorithms analysing multiple molecular tests promise even more precision. (Disclosure: I am an early-stage investor in a start-up working in the DNA diagnostics field.)
The day when somebody visiting a rural clinic in Africa, or an urban GP’s surgery in London, can be told within minutes – rather than days -- that they have latent tuberculosis, and whether or not it is drug resistant, will soon be on us, even if there are vanishingly few bacterial cells in the sample. The day when somebody can be told whether they have the genetic combination that makes them react poorly to warfarin or some other drug is coming fast, too. The earlier detection of cancer through non-invasive blood tests is also coming a bit more slowly. Early treatment of cancer not only saves lives; it saves money too. Stage 1 treatment for most cancers is one-third to one-quarter as costly as stage 4.
In other words, guessing at a diagnosis based on symptoms, or relying on distant laboratories, is being replaced with simple, sometimes hand-held devices in the clinic. For some hypochondriacs, this will be a moment of vindication. (“I told you I was ill” is the epitaph engraved on Spike Milligan’s headstone in Winchelsea.) For others, it will be a moment of humiliation. Quite a few of those who claim to have Lyme disease, or gluten intolerance, are imagining it and need to be told so. The quacks and alternative practitioners who foment their worries and plunder their wallets deserve to be put out of business by new diagnostic tests.
The counterproductive practice of prescribing antibiotics for colds, against which they are wholly ineffective, should also end. In passing, I remain surprised by how little impact the germ theory of disease has made on ordinary people’s thinking in the 170 years since John Snow first railed against the reigning obsession with blaming cholera on air pollution. To this day I meet hordes of people who insist that their colds were mainly caused by getting wet, or getting run down, or being unhappy, rather than by shaking hands with somebody who carried a virus.
There is a problem for Britain in this diagnostic revolution. For mainly historical reasons, the National Health Service can sometimes be profligate in the way it treats diseases, giving in too readily to the blandishments of drug companies with very slightly better, but much more expensive, versions of a treatment. But it is the opposite with diagnostics. The NHS is notoriously resistant to ordering “tests”, and is exceedingly parsimonious when it comes to buying new blood-diagnostic tools.
The statistics bear this out. The size of the in-vitro diagnostics market in Britain per head of population (not counting infrastructure) is less than half that of Germany and Italy, and about the same as Slovakia and Croatia. This, says the British In Vitro Diagnostics association, is partly because “the benefits of diagnostics are often either misunderstood, or worse, not considered at all” and “the NHS is too inflexible when it comes to adopting new IVD tests. Typically, solutions are still thought of as pharmaceuticals and consideration is not given to how IVDs could be adopted in the system to improve outcomes”.
For example, the leaders of the Northern Irish company, Randox, a pioneer in blood protein and genomic diagnostics, are frustrated with how little they are able to benefit their home market as opposed to overseas. They have tests that could save lives and money by earlier and fewer treatments. But the monolithic NHS cannot find it within its budget silos to buy such tests. Elsewhere in the world innovations that save lives and money are much more welcome.
In the main pathology field of clinical chemistry and immunoassay testing (~80% of all testing) only one new test has been widely adopted by the NHS in the past ten years: high-sensitivity troponin for detecting myocardial infarction or heart attack. That was adopted because a dominant private sector provider forced change on the sector. The NHS now values the test, but industry insiders say that left to their own devices, it is questionable how quickly even this test might have been adopted within the NHS.
Randox now has a complementary test for heart attack management, based on fatty acid binding proteins, but, though there is significant international interest, the firm is struggling to get the NHS to adopt it. The fatty acid proteins are released into the blood stream by damaged heart cells within 30 minutes, whereas troponin is released only when heart cells die after several hours. Combined with troponin, the test would more rapidly identify the one-fifth of patients with chest pain in Accident and Emergency who need treatment and the four-fifths who can be safely sent home, freeing up beds and saving about £225m a year.
Stem cells, gene therapy and gene editing promise a new generation of medicines for treating disease. But proteomics and genomics are transforming diagnosis into a cheap, rapid and accurate process that is probably going to have an even bigger effect on most people’s health. Britain is good at inventing this stuff, and selling it to the world, but terrible at applying it for the benefit of its citizens.
Matt Ridley, a member of the British House of Lords, is an
acclaimed author who blogs at www.rationaloptimist.com.