BBC Science Focus - 03.2020

COMMENT

fewyears ago, I made a film about
health tests for BBC’sHorizon.
I put myself through a battery
of health tests to see which, if
any, were worth doing. These tests
included things like having my blood
pressure tested, a CT heart scan (only
available privately), the prostate
specific antigen (PSA) test for prostate
cancer, and bowel scope screening
(they stick a camera up your backside
to detect early signs of bowel cancer).
I concluded that having my blood
pressure tested and my bowels
screened were a really good idea,
but that many of the other tests I did
were more likely to induce anxiety
than find out anything worthwhile.
The PSA test for prostate cancer
is a prime example of a test that can
do more harm than good. The reason
for doing it is that prostate cancer is
a major killer. While breast cancer
deaths have reduced by a fifth over
the past 10 years, the number of
men dying from prostate cancer has
increased by 18 per cent. Within the
next 10 years, prostate is predicted
to become the most commonly
diagnosed cancer in the UK.
So you can see the pressure to
detect it early. Yet not only does
the PSA test throw up lots of ‘false
positives’ (telling you that there
might be something there when there
probably isn’t), but it also warns you
about the presence of cancers that
would never actually impact your
life. Autopsies show that something

like 70 per cent of men over the age

of 80 have prostate cancer, but most

will die of something else.

My father is a prime example. He

had a PSA test in his early 70s and

was told he had prostate cancer. He

had invasive surgery to get rid of it.

The impact of the surgery blighted

the last years of his life. It’s possible

the treatment slowed the disease, but

it is also possible that it was a slow-

growing tumour and he would’ve died

never knowing he had it. In fact, he

died of unrelated heart failure a few

years after the operation.

MICHAEL

MOSLEY

Michaelis a writer

and broadcaster,

who presentsTrust

Me, I’m A Doctor.

Youcan watch

clips atbit.ly/trust_

me_clips

Healthtests may be useful,

but they can also lead to

anxiety and false positives

PROBING THE

PROSTATE

COMMENT

Several randomised controlled

trials have shown that if you have

a slow-growing tumour then it is

better to watch and wait than to have

surgery, radiation or hormone therapy.

But how do you know if your tumour

is growing slowly?

The good news is that tests which can

discriminate rapidly growing cancers

from more benign forms are becoming

available. These include something

called a ‘multi-parametric magnetic

resonance imaging’ (mpMRI) scan,

which creates more detailed pictures

of the prostate than a standard MRI

scan. These are available on the NHS,

and recent trials have shown that

having an mpMRI scan reduces the

chance of unnecessary biopsies and

aggressive treatments.

Since biopsies and over-treatment

often lead to impotence and urinary

incontinence, I will be booking myself

in for an mpMRI should the need

arise.

“ThePSA test for

prostate cancer is a

prime example of a

test that can do more

harm than good”

PORTRAIT: KATE COPELAND ILLUSTRATION: JASON RAISH

A