00:00
So how do you get lung cancer and the basic
answer is that you smoke cigarettes.
00:06
The exposure of cigarette smoke over time will
cause respiratory epithelium to acquire multiple mutations
and the effects of these on tumour suppressor
genes and oncogenes eventually end up with a
cell which is unable to be controlled by the
numeral physiological mechanisms and immune surveillance
of abnormal cells and will replicate and cause
a cancer. 90% of this cases are due to cigarette
smoking. There are other factors which also
will influence the development of lung cancer.
00:34
For example, we know that if we have been
exposed to asbestos in combination with smoking
cigarettes that become synergistic with increasing
your chance of lung cancer. We also know exposure
to radioactive gases such as Radon could increase
your chance of lung cancer and in fact in
Camborne in the UK, the houses built there
have to have a radon prevention membrane
built underneath them to prevent the radon
gas which is very common in Camborne seeping
into the house because of this risk of increase
of cancer. In addition, things are radiotherapy
to lungs, family history of cancer, various
chemical exposures apparently diesel exhaust
may increase your chance of cancer. They will all
contribute towards a chance of getting cancer.
01:15
An important point is that if you have chronic
obstructive pulmonary disease, i.e. smoking
rated lung damage. The chance of lung
cancer is increased over and above just the
effects of smoking itself. So there is something
about the inflammation is present in patients
with COPD which makes lung cancer more likely to
develop compared to smokers who don’t develop
COPD. But another important point, is that not all
of lung cancer
is due to smoking. About 10% occur in non-smokers
and there is a specific type of disease which
is adenocarcinoma which tends to resent in
non-smoking middle aged woman. What happens
is that if somebody will present with a bit of
cough, a chest x-ray will be done and it will
show multiple metastases of adenocarcinoma
througout both lungs and characteristic to that
would be a non-smoking population. So in general,
how would you recognize somebody
with lung cancer? Well, they tend to be
an elderly person like 75, the male slightly
more predominant than female. But actually
in females this lung cancer is still very
common as we said it's the commonest fatal cancer
in females, much more common than breast cancer
as a cause of death in women. So somebody
who smokes, who is aged over 50 years, has a
lung mass on the x-ray you must exclude cancer
as the cause. If they have systemic symptoms
which might suggest they have a cancer and
those are mainly weight loss, looking cachexic,
no appetite, fatigue, and general malaise
feeling ill and if they have specific symptoms
suggestive of a cancer such as cough or haemoptysis,
then your suspicions are even more higher.
03:02
So as we see in this, there is an x-ray where
somebody has a lesion on the top of their left
lung and a smoke. You must think
that lung cancer is the potential cause for
that in this situations and may not be the
cause but it needs to be excluded.
03:17
The major problem with the clinical presentation
of lung cancer is that the symptoms the
patients present with are very, very variable. As a
consequence they can present to any specialty.
03:28
Not just chest physicians, they can present to
neurologists, to bone doctors etc etc. and
as a consequence everyone who deals with
patients who are in the age range which
may have cancer, needs to be aware of lung
cancer's potential diagnosis.