While developing devices to capture X-rays from objects in space,
scientists at the European Space Agency have designed a camera that could
become a powerful new weapon in the fight against cancer.

Effective treatment of cancer relies on the early detection and removal of
cancerous cells. Unfortunately, this is when they are hardest to spot.
In the case of breast cancer, now the most prevalent form of cancer in the
United Kingdom, cancer cells tend to congregate in the lymph nodes, from
where they can rapidly spread throughout the rest of the body. Current
medical equipment can give doctors only limited information on tissue
health. A surgeon must then perform an exploratory operation to try to
identify the diseased tissue. If that is possible, the diseased tissue
will be removed. If identification is not possible, the doctor may be
forced to take away the whole of the lymphatic system. Such drastic
treatment can then cause side effects, such as excessive weight gain,
because it throws the patient’s hormones out of balance.

Now, members of the Science Payloads Technology Division of the Research
and Science Support Department, at ESA’s science, technology and
engineering research centre (ESTEC) in the Netherlands, have developed a
new X-ray camera that could make on-the-spot diagnoses and pinpoint
cancerous areas to guide surgeons. Importantly, it would be a small
device that could be used continuously during operations.

“There is no photography involved in the camera we envisage. It will be
completely digital, so the surgeon will study the whole lymphatic system
and the potentially cancerous parts on his monitor. He then decides which
parts he removes,” says Dr. Tone Peacock, Head of the Science Payloads
Technology Division.

The ESA team were trying to find a way to make images using high-energy
X-rays because some celestial objects give out large quantities of X-rays
but little visible light. To see these, astronomers need to use X-ray
cameras. Traditionally, this has been a bit of a blind spot for
astronomers. ESA’s current X-ray telescope, XMM-Newton, is in orbit now,
observing low energy, so-called ‘soft’ X-rays. European scientists have
always wanted to follow up XMM-Newton’s success with a satellite called
XEUS. It would be capable of taking images of the high-energy ‘hard’
X-rays but a reliable camera has eluded them – until now.

For the first time, the ESTEC researchers have produced a microchip,
similar to that found in a household video camera but capable of detecting
hard X-rays instead of visible light. The key is that, instead of
silicon, the new chip is made from a chemical compound called epitaxial
gallium arsenide. This new material was developed under the ESA leadership
of Dr Marcos Bavdaz to the very demanding requirements of such hard X-ray
sensors. The prototype sensor has now successfully completed its
extensive tests at a German X-ray test facility (HASYLAB).

It may seem surprising that medical imaging is similar to observing high
energy X-rays from space. However, hard X-rays are the only type that
will pass through the human body.

Dr Alan Owens, who is closely involved in the research at ESA, explains:
“For the lymphatic system a radioactive tracer which emits X-rays is
injected into or near the breast tumour. The tracer focuses on those parts
of the system which are cancerous. With a small camera it is therefore
possible to image this cancerous tissue during surgery.”

The ESA team were aware, from an early stage, that the work they were
doing could lead to better medical equipment and sought expert advice.
“We are talking to the people at Leiden University Medical Centre,”
explains Owens. “Also they can test and evaluate what we produce.” A small
lightweight X-ray camera would be a very important addition to the set of
tools available to the surgeon.

Having made the basic camera sensor, the next stage in this work is to
develop a system to send the images to television screens in real time.
“We are developing that now with our industrial partners, such as Metorex,
a research and development company in Finland,” says Peacock.
Once ESA, which is a non-profit organisation, has developed the technology
to make this X-ray camera work, its task is done. The industrial partners
will take over, producing a camera for medical use. ESA will adapt its
design to provide European astronomers with a new view of the Universe.

For further information please contact:

ESA – Communication Department

Media Relations Office

Tel: +33(0)1.53.69.7155

Fax: +33(0)1.53.69.7690

Dr Tone Peacock, ESA – ESTEC,

Noordwijk, The Netherlands

Tel: + 31 (0)71 565 3563

Anthony.Peacock@esa.int

Dr Marcos Bavdaz, ESA – ESTEC,

Noordwijk, The Netherlands

Tel: + 31 (0)71 565 4933

Marcos.Bavdaz@ea.int

Dr Alan Owens, AURORA c/o ESA – ESTEC,

Noordwijk, The Netherlands

Tel: + 31 (0)71 565 5326

Alan.Owens@esa.int

Professor E.K.J. Pauwels, Leiden University Medical Centre

Nuclear Medicine, Leiden, The Netherlands

Tel : +31 (0)71 526 3475

E.K.J.Pauwels@lumc.nl

Dr J.A.K Blokland, Leiden University Medical Centre

Nuclear Medicine, Leiden, The Netherlands

Tel : +31 (0)71 526 3485

J.A.K.Blokland@lumc.nl

For more information on the ESA Science Programme, visit the ESA Science
website at: http://sci.esa.int