Laser light
in combination with certain drugs – known as photodynamic therapy – can destroy
cancer tumours, but is today used mostly to cure skin cancer. The reason that
internal tumours are not treated with the method is that the technology does not
exist to check that the precise amount of light is administered. However,
software developed by researchers in atomic physics at Lund University in Sweden
looks like being able to solve the problem.
“I think we are
about to see a real breakthrough, both for us and for other research groups
around the world who conduct research on cancer treatment using laser light”,
says Johannes Swartling, Doctor of Atomic Physics at Lund University and Chief
Technical Officer at SpectraCure, the company that is now developing the
software.
The software’s unique feature is that it uses the optical
fibres for more than simply emitting light. Intermittently they also gather
information about the tumour, which they send back to the laser
instrument.
“In this way, the software can continually calculate the
optimal light dose and adjust it if necessary. The entire tumour must be
removed, while damage to adjacent organs must be avoided”, says Johannes
Swartling.
According to the researchers, the software could also be used
with other light therapies that use LEDs or infra-red lasers.
Tests on
prostate cancer patients in Sweden have shown that the method also works for
internal tumours, and in the spring a clinical study on recurrent prostate
cancer will begin in the US and Canada. An application for approval to carry out
the study is pending. Meanwhile, the same laser light technology is being tested
in the UK on pancreatic cancer.
“The advantage of laser light is that it
appears that side effects can be minimised. With current treatment methods,
prostate cancer patients who are cured risk both impotence and
incontinence.”
In addition, traditional treatments entail a risk of
cancer recurrence, says Johannes Swartling.
The international tests focus
on adjusting dosage, guaranteeing safety and ensuring the effectiveness of
treatment. If everything goes smoothly, SpectraCure hopes the method will be
approved by the US Food and Drug Administration and Health Canada within a few
years.
“This really could be revolutionary”, says Sune Svanberg,
Professor of Laser Physics at Lund University and one of the researchers behind
the technology.
“The new technology has great potential to help certain
patient groups, for whom current treatment methods have major limitations”, says
Professor Dr Katarina Svanberg, Department of Oncology, Lund University, who has
been involved in the medical side of the development of the method.
How
photodynamic therapy worksBefore the procedure, the patient is given a
light-activated drug, which has no effect without light. The drug spreads
throughout the body, including to the area of the tumour. The patient then
receives a local or general anaesthetic and the doctor inserts needles with
optical fibres into the area affected. These channel light into the cancer
tumour. When the light comes into contact with the light-activated drug, it
reacts with the surrounding oxygen, causing the cells in the target area to
die.
The hardware and software are based on patents developed by atomic
physicists in Lund, led by Sune Svanberg and Stefan Andersson-Engels. The idea
was to allow the same optical fibres used for treatment to be used for
diagnostic measurements that make it possible to calculate the light dose
required. The method was soon seen to be practicable and has been developed over
the years, now by SpectraCure. The implementation has been carried out by
programmers.