inject the substance into the arteries through a venflon catheter and
then it flows around with the blood and becomes trapped in the bone
metastases, where it accumulates. From here it emits alpha particles.
The alpha particles have so much energy that they destroy the cells each
time they hit one, although the impact also slows them down them a
little. After 6-10 cells the particles stop completely, but they have
completely destroyed the cancer cells they have hit," explained Jann
Mortensen, who is a Consultant at the Department for Clinical
Physiology, Nuclear Medicine and PET at Rigshospitalet.
substance injected into patients is called Radium 223 and it is only
administered in very small doses. It was not permitted to use Radium 223
in treatment until 2013.
"This is the first time we have been
able to treat patients with alpha radiation. Previously, all other
treatment has been with beta radiation. We treat more or less the same
types of patients with alpha radiation as we did with beta; that is
patients with prostate cancer with bone metastases, but beta radiation
only helps pain relief; not survival. This is the first time a treatment
has proven so effective that, in addition to pain relief, a patient
also has a better chance of survival, and that's what makes this new
treatment so exciting," said Jann Mortensen.
A mild but effective killer
radiation is an effective weapon against cancer cells. Yet alpha
particles have fewer side effects because they are slowed down so
rapidly that they do not reach healthy tissue, whereas the same
treatment with beta radiation gets further out to healthy tissue and
causes damage. Therefore, the new treatment avoids damaging a lot of
normal tissue, and this leads to fewer side effects. Despite the fewer
side effects, patients still have to meet some requirements before they
can receive the treatment.
"You have to have sufficiently strong
bone marrow function to tolerate the new treatment. It doesn't have to
be completely normal, but it must be reasonably good. We assess from
treatment to treatment. Before each treatment we check patients to
ensure that we can go on with the next treatment," explained Jann
Extensive safety procedure
course of treatment stretches over five months, during which the patient
receives six treatments in total. Two laboratory technologists from the
Department of Clinical Physiology Nuclear Medicine and PET will be
conducting the treatment. The treatment involves extensive safety
measures, which among other things mean that treatment personnel have to
be checked for background radiation several times a day.
have to go through an extensive procedure every time we perform a
treatment, but it's important that we protect our personnel and ensure
that they do not become contaminated. Our permit to use alpha radiation
is also conditional upon personnel being closely monitored," said Jann
Mortensen, who expects to have his first patient undergoing treatment
just after Easter.
First treatment site in Denmark
is the first place in Denmark to be granted authorisation to perform
treatment with radioactive alpha particles, so until other hospitals in
Denmark are also granted permits to perform the same treatment,
Rigshospitalet will have to accept patients from throughout Denmark. In
the long term the ambition is that Rigshospitalet will only receive
patients from the Capital Region of Denmark.
in Denmark have estimated that around 150 patients a year will need
treatment, but it is really too early to say, as the treatment is so new
and its potential has yet to be fully determined. In the long term,
however, Jann Mortensen believes that alpha radiation treatment could
become more widespread and include other types of cancer.
treatment has so far only been approved for prostate cancer and bone
metastases, but there are many other types of cancer which also spread
to the bones, so in principle it will also be possible to treat all
types of bone metastases. Trials with breast cancer have been initiated,
and if these prove positive, this will probably be the next cancer type
for treatment. Breast cancer patients are a large group and many also
get bone metastases, so alpha radiation will be a valuable treatment for