The asbestos-cancer Mesothelioma
We have been researching this disease
for around 15 years. Here are some details of the disease.
What is
it?
What
causes it?
How
does it happen?
What tests are done?
What
treatment is available?
What is
mesothelioma?|
Mesothelioma is a malignant tumour (a cancer) which arises in the
thin tissue which forms a sac around the lung (the “pleura”),
abdomen (the “peritoneum”) or heart (the “pericardium”). The tumour
most commonly occurs in the chest (“pleural mesothelioma”).
Pleural mesothelioma is quite distinct from pleural plaques
(which are benign, scarred regions of the pleura), is different from
asbestosis (which represents scarred non-cancerous scar tissue
of the lung itself) and is different from lung cancer (which
represents cancer arising in the lung tissue rather than the
pleura).
What
causes mesothelioma?
The
commonest cause of mesothelioma is asbestos. The most dangerous form
of asbestos is blue asbestos (crocidolite) although brown asbestos (amosite)
and other forms of asbestos can also cause mesothelioma. White
asbestos (chrysotile) is less likely to do so, although it is often
contaminated with mesothelioma-causing types of asbestos. All forms
of asbestos can cause asbestosis and, particularly in smokers, lung
cancer. There are other less common causes of mesothelioma eg. some
man-made mineral fibres, radiation etc.
How
common is mesothelioma?
Mesothelioma was a rare disease but since the 1960’s there has been
an “epidemic” of this disease. There are currently 10-20,000 cases
per annum throughout the world and the incidence continues to
increase each year. Of great concern is the fact that between 20
and 35% of all patients have never had “significant” exposure to
asbestos ie. they represent ordinary individuals from the population
who presumable have inhaled asbestos fibres in the past but who
cannot recall such exposure. The Australian federal government (Worksafe)
have predicted that mesothelioma will kill more Australians than
AIDS.
How
long does it take for mesothelioma to appear?
Whilst
asbestos fibres can damage body tissue immediately, it takes many
years before a cancer finally breaks out. Whilst in some cases this
interval can be as short as 10 years, generally it is 30 years or
more. During this “incubation period” the asbestos fibres are
presumed to be gradually damaging the body’s cells and the cancer
only breaks out when sufficient damage has been caused to turn the
cell into a cancer cell. Unfortunately at the present time there
are no tests available to detect such changes early, although
current research is attempting to develop such a test.
Who
gets mesothelioma?
Currently about 70% of those who develop mesothelioma have had clear
exposure to asbestos at some time in their life. Most have been
exposed to asbestos either during its mining, milling and transport
or when it has been used in industry (eg. by plumbers, carpenters,
ship builders, naval personnel, builders) or as wives of
asbestos-exposed workers, people living near asbestos industries,
children exposed to asbestos in the environment etc. Of the 20-35%
of patients with mesothelioma who have no significant exposure to
asbestos, it is assumed that they have had incidental exposure from
the environment as most of these people, like most people in the
community, have millions of fibres in each of their lungs. Many
cases are young adults.
Mesothelioma is not contagious.
How
is mesothelioma diagnosed? What tests are done?
There
are two main techniques used by doctors to diagnose mesothelioma.
Firstly, by xrays. Chest x-rays may show a lump or an accumulation
of fluid outside the lung tissue (mesothelioma tumours can ooze
fluid, induce inflammation and possibly block fluid removal). Often
a special xray called a CT scan (“computerised tomography”) will be
performed. This involves the patient laying in a xray tube whilst a
special xray machine takes multiple images and generates a computer
analysis. Secondly, and most importantly, doctors will need to
obtain some tissue for examination to prove that it is indeed
mesothelioma. This may involve a combination of examination of
cells obtained from a fluid collection from a tumour using a needle
(“cytology”) and direct examination of a piece of the tumour
obtained from a pleural biopsy, from a pleuroscopic biopsy (a doctor
looks into the chest cavity through a tube) or, in some cases, from
tissue obtained after surgical opening of the chest wall to directly
view the pleura.
A
number of complicated laboratory tests are undertaken to confirm
that the tumour is indeed mesothelioma rather than some other form
of tumour or other type of tissue reaction. With these modern
techniques it is usually possible to be fairly certain that the
diagnosis of mesothelioma is correct.
What symptoms does
mesothelioma cause?
Many
patients have no symptoms at all and their tumour is detected on
routine chest xray eg. for an insurance exam or for an operation.
Most patients present with either breathlessness (usually due to
fluid accumulation within the chest) or some chest wall pain
(assumed to be due to irritation of chest wall nerves by the
tumour).
If
the mesothelioma occurs in the peritoneum, swelling of the abdomen
often occurs and, in some cases, disturbance of bowel function.
If
mesothelioma occurs in the pericardium (surrounding the heart) then
it can exert pressure on the heart and limit its function leading to
breathlessness and tissue swelling eg. in the ankles.
What
is the prognosis?
Unfortunately mesothelioma is a very aggressive tumour and the
average survival from diagnosis is about 9-12 months. Of course
that only represents the average so many patients will live longer
than that eg. 12-18 months whereas others will unfortunately live
for less than that eg. 3-5 months. In general if the tumour is
detected early in an individual who is relatively young and healthy
then survival is longer than those who present with more advanced
tumours. Whilst occasionally patients live longer than two years,
this is very uncommon.
Usually patients remain fairly well for a large proportion of the
time of the illness. Pain can be controlled by modern medications,
as can breathlessness.
What
treatment is available for mesothelioma?
There
are three standard treatment strategies for any cancer, surgery
(remove it), radiation therapy (destroy the tumour cells by x-ray
beams), or chemotherapy (“poison” the tumour cells with drugs that
block the function of dividing cells). Unfortunately none are
effective in mesothelioma. Surgery is ineffective because the
tumour has always spread throughout the pleural cavity at the time
of presentation and it is impossible to remove it all. Even
removing most of the tumour does not really improve survival and
simply adds another operation to the list of things a patient must
undergo. Surgery can be very useful for controlling fluid
accumulation. Radiation is rarely used because this tumour is very
resistant to it, although again they can help alleviate symptoms in
some circumstances.
We
have developed a chemotherapy protocol here in Perth based on our
research program. This involves using several drugs which we have
shown to be capable of killing mesothelioma cells in the test tube.
Whilst this type of therapy has a good chance to shrinking
mesothelioma tumors and reducing symptoms, it is fair to say that at
this stage any benefits are only temporary.
A
number of experimental immunotherapy treatments for mesothelioma
have been utilised at the Sir Charles Gairdner Hospital and these
are offered to patients on a volunteer basis. Whilst each of these
treatments has had some success (eg. 10-20% of patients get major
shrinkage of tumour and a small proportion of these patients have
lived for over 5 years), it is important to realise that these
treatments are experimental and most patients who undergo them do
not respond. Doctors at the Sir Charles Gairdner Hospital can
provide you with specific information regarding these treatment
approaches.
What
about alternative treatments for mesothelioma?
Individuals with mesothelioma often ask about potential therapeutic
value of different diets, meditation, alternative non-standard
therapies etc. In general it is important that individuals
diagnosed with this disease maintain a good well-balanced diet, a
regular exercise program and continue with a positive approach to
life. In our opinion these are important and can prolong survival
to some extent. We have not however noticed any additional benefit
in those individuals who have utilised any of the above alternative
approaches. We continue to remain open to the possibility that new
ways of improving the prognosis for patients with mesothelioma may
be found, however we do not believe that there is any additional
benefit to the above approaches at this stage. Of course we respect
any patients right to choose whatever management strategy they wish
to choose and we will always continue to provide the best of care in
the traditional medical setting even if alternative approaches are
tried by patients.
What
is the Mesothelioma Research Unit?
This
unit has been established in the University Department of Medicine
and Department of Respiratory Medicine at Sir Charles Gairdner
Hospital.
Because of the widespread exposure of Western Australians to blue
asbestos, mesothelioma is unfortunately common in this State.
Doctors in many disciplines have substantial experience in studying
this disease. Over the past 15 years or so we have applied the
latest technological developments in medical research to this
disease and have established a program of research aimed at trying
to understand exactly how mesothelioma cells grow, why they are not
destroyed by the body’s immune defences and how we can destroy the
tumour effectively. This involves a mixture of laboratory research
and clinical treatment trials in patients with the disease. The
group has published hundreds of papers on mesothelioma in
international journals and has written numerous books as well as
book chapters on their work, as well as presenting their work at
many international conferences and overseas institutions. The unit
has been internationally recognised as a world leader in this field.
“The mesothelioma research done in this unit in Perth leads
the world. We have admired their work for years”.
Dr LK,
Philadelphia, USA.
What
can I do to help mesothelioma research?
The
sophisticated laboratory research and the clinical trials in
patients with mesothelioma are very expensive to undertake.
Substantial research funds are hard to acquire in Australia so
continued support is always a priority.
If
you wish to help you could donate to the research directly and/or
arrange a bequest to the research.
For further information
On
the Mesothelioma Research Unit
(Web address is:
http://www.meddent.uwa.edu.au/medicine/groups/
(click on ‘Tumor Immunology Group’)
On
diagnosis and treatment:
Contact your own local GP and/or your chest specialist.
On
cancer services available in Western Australia:
Contact the Cancer Foundation of Western Australia at
334 Rokeby Road,
Subiaco Western Australia 6008
Phone:
13 1120
On
asbestos diseases support services available in Western Australia:
Contact the Asbestos Diseases Society at
483 Charles Street, North Perth
Western Australia 6006
Phone:
9444 6699
On
the work of the Mesothelioma Research Unit:
Contact the Secretary,
Mesothelioma Research Unit
University Department of Medicine
QEII
Medical Centre,
Perth Western Australia
6009\
Phone:
9346 2005
Donating
to the Mesothelioma Research Unit
If you
wish to either donate money or make a bequest to support the work of
the Mesothelioma Research Unit, please
Send a
cheque or money order to:
Secretary, Mesothelioma Research Unit
University Department of Medicine
QEII
Medical Centre, Nedlands Western Australia 6009
Telephone: 9346 2005/9346 2098. Fax: 9346 2816
Cheques should me made out to “Mesothelioma Research Unit - SCGH
Account 2201”
Donations over $2 are tax deductible and a receipt will be forwarded
to you from the hospital accountant.
Arranging a bequest
A
bequest represents a statement in your will that you wish to make a
donation of a specific amount to the Mesothelioma Research Unit.
1. If
you have not already made a will this can be done either through a
lawyer or you can make your own will (will forms are available from
newsagents or stationers), although you will need two independent
adult witnesses who are not beneficiaries of the will to sign the
will at the same time, with the same pen in the same room.
2. You
should list the beneficiary as “Mesothelioma Research Unit - SCGH
Account 2201”, University Department of Medicine, QEII Medical
Centre, Nedlands 6009.
3. You
should inform the executor of your will of your request.
If you
would like to receive further information or assistance regarding
this please contact the secretary:
Secretary, Mesothelioma Research Unit
University Department of Medicine, QEII Medical Centre
Nedlands, Western Australia 6009
Tel 08 9346 2005 or 9346 2098
