The UK has poor cancer care compared with our neighbours. This fact is used as a stick to beat GPs especially, and has led to a huge investment in hospital cancer care in the last five years. But can we trust the stats, and has the investment been a good idea?
First of all we need to examine whether we really are making fair
comparisons, and what factors other than quality of care affect the results. We
generally compare survival figures such as the percentage of patients alive 5
years after diagnosis of a particular disease. There is an obvious problem with
this approach if the patients in one country differ at the outset from those in
another. This happens in various ways.
First of all, cancer of any particular organ is not one disease
but a collection of different mutated cell types that have changed in a way
that allows them to evade the immune system and invade other tissues. Some
cancers are much more deadly than others and some countries may suffer deadlier
subtypes more than others. For example, one type of lung cancer, so called
small cell, is never curable by surgery, and has a 5 year survival near zero. A
high proportion of this type among lung cancers will adversely affect overall
lung cancer survival. Cancer types do vary between European countries, so this
a significant problem.
Another problem is so called incidentalomas. These are true cancers under the
microscope, but do not behave as cancers, and rarely pose a threat to life.
These are not rare, with kidney cancer, thyroid cancer, skin cancer, and so
called Ductal Carcinoma of the breast being well known examples. In countries
where more formal or ad hoc screening scans are done, a proportion of 5 year
survivors are not surviving because of good treatment, but because they would
have been alive anyway because their ‘cancers’ were never a threat to life.
Then there is so called 'lead time bias'. If patients are
diagnosed earlier, they are more likely to survive for 5 years, even if there
is no effective treatment, simply because the diagnosis is made earlier in the
natural course of the disease. This problem is well known but it is difficult
for experts to allow for it.
A useful example is Prostate Cancer compared between the US and
the UK. The death rate of this condition has remained similar and very stable
in both countries for many years. But the survival figures have improved
dramatically in the U.S. The general interpretation is that U.S. Patients are
getting a diagnosis, which is of more harm than benefit, and that treatment is
largely useless at least in terms of postponing death.
Then there is the issue of cancer registries and death
certification, especially of elderly patients who are likely to have advanced
cancer, but who are frail and generally sick. These patients and their families
may choose not to have scans or operations and they may therefore never be
included in the statistics. This tendency is likely to vary between countries.
A large proportion of patients are certified as dying of 'old age', some of who
surely in reality died of cancer. Some countries have much higher rates of post
mortem examinations than others. In those countries the true cancerous
diagnosis will be recorded, thus adversely affecting survival statistics.
Then there is patient behaviour, which varies significantly. For
example, lung cancer survival is strongly affected by whether smokers stop the
habit. Other variables, such as Vitamin D blood levels are also known to have a
major effect (so if you get cancer, move somewhere sunny). Behaviour in terms
of the way patients seek medical advice is also important. Anecdotally, there
seem to be 2 main types of patients in the UK, the 'worriers'-those who listen
attentively to the health info publicity, and seek advice for every skin
blemish or headache because it might be cancer,- and a significant number of
'deniers' who ignore symptoms like weeing blood. If a country has a higher
level of health literacy, and more sensible behaviour, then it is likely to
result in earlier diagnosis and better survival.
Another relevant variable factor is the extent to which patients
accept definite harms in the hope of an improved chance of long term survival.
For example, patients with early localised breast cancer may be offered drugs
and radiation with the aim of mopping up cells that may have spread, even
though that may be relatively unlikely, so that only a small minority of patients
are likely to benefit. Patients and their doctors in some countries will
conclude that it is worth taking the small risk of not having the
treatments, in order to avoid the
certainty of months of feeling ill, losing hair etc. This will worsen the
statistics for that country but does that mean that the standard of care is
worse?
Taking the survival figures at face value has led to various
actions in the UK. Cancer patients are now treated by so called MDT's, where
the surgeons, oncologists, X-ray specialists etc. discuss patients and decide
on treatment. This has been done in order to improve survival. But this ignores
one of the most important principles of medical ethics, which is patient
autonomy, the freedom to make ones own choices with ones body. It also commonly
leads to severe communication failures, for example patients attending for
follow up appointments at which the doctor that sees them assumes incorrectly
that the patient has already been given some bad news, for example that a
cancer has spread. This seems unbelievable but I personally have encountered
this several times in the last 3 years just among my own patients.
Also, patients seem to be being pushed into treatment with drugs
which reduce their quality of life, when the prospects of extending their lives
seem very poor. it seems that the imperative to improve the stats is once again
going against standard medical ethical principles.
One suggestion made by our Health Minister on this issue, has
been to 'name and shame' individual GPs who fail to refer patents within the
first couple of consultations, or if their patients are diagnosed after being
admitted to hospital as an emergency. This is a naive idea. First of all
measuring this statistic per individual GP would be tricky, as defining which
consultations counted would not be obvious. Also each doctor will only refer a
handful of patients every year who are found to have cancer, and there would be
a lot of random variation. But the main problem is that once again cancer is a
mixed bag and certain types (pancreatic cancer for example), are very difficult
to diagnose, while others are easy.
Once again there is a big risk of comparing apples and pears.
There is however one very obvious factor that is associated with
better survival rates, which is short waiting times for 'routine' scans and
specialist appointments. Results for the UK and Denmark, which both rely on GPs
as gatekeepers to assign priority to patients, are poor.
The reason is that medicine is a difficult art, and a large
proportion of patients in all countries are diagnosed with cancer after routine
investigation of vague complaints rather than so called red flag symptoms.
Reducing waiting times for these patients, and loosening the tick box restrictions
on urgent referrals would certainly improve performance, but at a huge cost and
of course not within the tenure of any particular minister. Blaming GPs is easier.
So should we ignore the figures? No of course we should not, but
like all statistics they should be examined carefully and suspiciously and kept
away from politicians and never used as soundbites.
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