well welcome to another MedCram lecture at med cram comm good to talk about lung
cancer staging so once you've made a diagnosis of lung cancer there's two
major types of lung cancer the first one that you should know is something called
non-small cell lung cancer and what are the types of non-small cell lung cancer
you've got squamous you've got adenocarcinoma and you've got large cell
now another type of adenocarcinoma is known as bronchial alveolar carcinoma
which name has recently changed to an O carcinoma in situ typically looks like
ground glass opacification squamous cell carcinoma
it's your p63 positive cytokeratin five and six positive usually has
hypercalcemia typically at the later stages if that's the case it's going to
be positive for the parathyroid hormone-related peptide which is a
paraneoplastic syndrome for small cell which is the second type so not
non-small-cell but small cell lung carcinoma this is the small blue cell or
oat cell as it used to be called and it can have a paraneoplastic syndrome of
various different things it could be eaten Lambert syndrome you could have a
SIADH or even a Cushing syndrome type and so these two are very different the
small cell lung carcinoma typically is more aggressive than non small cell lung
carcinoma is not as aggressive in some cases you can even cure these if they're
found early enough so the way that we're going to talk about this is usually the
something called the T or the tumor the N or the node and the EM stage now these
combined to give you your overall stage which will determine the treatment for
lung cancer so the T stands for tumor or tumor size the n is how many nodes are
positive and the M is if there are metastases and where the metastases are
you can use the T mmm for small cell lung carcinoma but it's
actually not as useful typically we use something called limited or extensive
staging we can talk about that in another lecture where the T and an M
staging is used almost exclusively is in a non small cell lung carcinoma so
that's what we're going to talk about is the staging for non small cell lung
carcinoma and the reason why this is important is because there are different
treatments for each of the overall stages so I don't want you to get
confused there is a T stage there is an end stage and there is an M stage and
then we put those all together and we come up with a total stage and so the
question is how does that happen well I want to explain that to you because it
is a somewhat complex way of doing it and you always wonder well how do they
come up with the overall stage from a T and an M staging so let's get into that
what we have here is the T stages so there's a t1 a a t1 b a t2 a at e2 b and
a t3 and finally a t4 that is combined with n 0 through n 3 stages has to do
the lymph nodes and then finally there is a m0 m1 a and an m1 B and those will
give us our stages so the first thing I want to do is I want to talk a little
bit about the T stages and now the T stages have to do with the actual tumor
itself so generally speaking a t1 a is any tumor that is less than 2
centimeters in size a t1 b is anything that is 2 to 3 centimeters inclusive i
put a underline there a t2 a would be anything from 3 to 5 centimeters a t2 B
would be 5 to 7 centimeters a t3 is 7 plus centimeters and by the way these
are inclusive here and then finally a t4 is anything that is large it involves
the mediastinum so if you have invasion of the
mediastinum structures of the beanie Steinem for instance the trachea or the
esophagus and sometimes there are multiple different things that are going
to be included and so you always pick the worst okay now there are other
things that can give you a t2 a or a t to be for instance if and these are sort
of combined here so I'm going to erase this little dividing line okay because
this would put it into a t2 stage anything that is greater than two
centimeters from the karana remember what the corona is it is where
the trachea divides into the two main stem bronchi so if there's a main stem
bronchi tumor if it is greater than two centimeters from the Carina it could fit
into the t2 stage anything that causes a lobe to collapse okay as opposed to a
whole lung to collapse or anything that causes a lobe or anything that involves
the visceral pleura now that's opposed to anything that is
less than 2 centimeters from the karana which would be at t3 anything that
causes a lung to collapse or anything that involves the parietal pleura okay
visceral pleura parietal pleura now there is one more thing that could give
you a three and I'll put it up here and kind of pink so you can see it but if
you have two nodules in the same lobe obviously in the same lung what could
give you a t4 is if you have two nodules in different lobes of the same lung okay
so for instance if you had a nodule that you found or cancer that you found in
the right upper lobe and in the right lower lobe they would be two nodules
that are different Loubs but in the same law that would get
you into a t4 regardless of how big they were however if you had two nodules that
were in the right upper lobe they would be in the same lobe same lung that would
get you to a t3 okay so we're looking for the worst combination if you had
complete collapse of the right lung that would get you a t3 because you have
complete lung collapse if you had something involving the chest wall that
is the parietal pleura that would get you a t3 so the first thing you need to
do whenever you see a tumor is figure out what T level it's going to be once
you figure out what T level it is then the next thing you need to do is you
need to figure out what the N level is so n o means that there are no nodes
involved so you can find that out early by looking at a CT scan to see if there
are enlarged lymph nodes you can somewhat confirm that by getting a PET
scan to see if those nodes light up or not but if it makes the difference
between surgery or no surgery you really want to confirm that with either a
mediastinum skippy which is more invasive or which is less invasive would
be EBUS okay that's endoscopic bronchial ultrasound
where you actually go down there and take a sample with a needle so if you
have a tumor on the right side and you see no nodes so no EPSA lateral lymph
nodes mediastinal lymph nodes so coronal lymph nodes then you would get an n zero
which is very good if you however you had hilar lymph adenopathy and these are
going to be double digit numbers if they tell you it's lymph node number 12 L
that means on the left side it would be the 12 lymph node anything with double
digits is gonna get you out into the hilum which is pretty peripheral and if
that's involved that would be an n1 if on the other hand you are talking about
mediastinal lymph nodes so not hilar but mediastinal that would be an N - those
are just typically single digit and that would also include sub coronal
okay sub coronal lymph nodes so mediastinal or sub coronal lymph nodes
is going to be an N - typically single digit lymph nodes and three would be
back again - double digit but it would be contralateral so this is not good
this would be where you have a right-sided tumor but a left-sided lymph
node that is lighting up that would be an n3 so that would be a hilar lymph
node on the other side could also be double digits okay and then mo would be
no metastasis anywhere else okay so no mats so the default would be zero
there's two situations that would get you an m1 a number one if you had a
malignant pleural effusion so if you did a thoracentesis and sent the cells off
or cytology and they were positive that would give you a malignant pleural
effusion you would be at a stage m1 a another way is if you had two nodules in
different lungs so again if you have two nodules in the same lobe right upper
lobe that would be a t3 if you had two nodules in the same lung but different
lobes that would be a t4 if you have two nodules in different lungs so right
upper lobe left lower lobe for instance that would give you a m1 a and m1 B
would be anywhere outside of the chest and I'll just say that if you meet the
criteria unfortunately for m1 a or an m1 B that's an automatic stage for we're
going to write these stages in Roman numerals so regardless of your N or T if
you meet any of these criteria you're automatically at stage 4 so that's
important because if you've got a patient with a malignant pleural
effusion that automatically puts them at a stage m one-a which automatically
gives them a stage 4 okay so let's go through these
stages so the first stage that you're going to have is overall stage 1a and
that's going to be here 1 a and 1 a this would be 1 B and that's
where it would end the next stage you would have is 2a and 2b down here you
would have 2a 2a and 2a this would be 2 B this would be 3 a this would be 3 a
and this also would be 3a all of these down here are 3 A's except for one this
one here is 3b and of course all of these along here are also 3b
join us for the next video when I talk about how to remember this and the
mnemonics and the treatments for all of these stages thanks for joining us and
join us at med cram com
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