00:02
Thymomas.
00:03
A tumor of thymic
epithelial cells perhaps.
00:07
Admixed non-neoplastic
lymphoid cells maybe present.
00:11
Easily confused with a lymphoma
because you’re not expecting to find
a large thymus in an adult perhaps.
00:20
Stages:
I, encapsulated.
00:23
II, microscopic, only locally invasive.
00:27
You get into stage III,
now, we have issues.
00:31
Pay attention here.
00:33
Let’s say that thymus is
undergoing enlargement due to,
well, a thymoma, maybe a tumor.
00:40
Think about the surrounding structures
of the thymus in the mediastinum,
and you might start invading
into the pericardium,
great vessels or
perhaps even the lung.
00:50
Of all the stages with thymoma,
you focus upon stage III, please.
00:55
Stage IV will be the same
basically in any type of cancer
where it then goes
onto metastasis.
01:03
In this table for staging or histological
description of the thymomas,
there are different types.
01:10
A little bit more detail than
what’s necessary for you but
you might get an idea as
to what you can expect,
especially the last column where it
says disease-free survival at 10 years.
01:20
That’s what you’re
paying attention to.
01:23
A, AB,
83, 83.
01:27
Now, this is where you
want to pay attention to.
01:29
As you go from B2 to B3,
is where you’ve dropped from
83 to 35, that is significant.
01:39
There’s a theme here or concept that
you need to take away from medicine.
01:43
Anytime that you’re dealing with any cancer,
I can only give you so many angles.
01:48
And from the feedback that I’ve gotten,
it’s the fact that ultimately,
it’s where you’re looking at
prognosis where it’s decent
to perhaps even good and
it drops dramatically.
02:00
Those are the staging types that
you want to pay attention to.
02:03
B2 to B3, you’re not
going into carcinoma,
you’ve dropped down to 35.
02:09
And as you go into C, well,
further thymic carcinoma.
02:17
Now, when there is thymoma
on chest x-ray in an adult,
so let’s say that you have a female
and she says, “Hey, doc. I wake up in
the morning and I’m feeling fantastic.
02:29
And by the time the day
is coming to an end,
well, the first thing that happens
is just every single day,
I just have a hard time
looking at the computer
and I feel like I can’t
even open up my eyelids.
02:43
And really, by four or five o’clock,
forget about it, I can barely
even get out of my chair.
02:49
On chest x-ray, you’ll find an
enlargement in the mediastinum.
02:55
So therefore, this will be a thymoma.
02:57
Surgically, oftentimes, this thymoma
in adult, why did I give you a female?
And what kind of symptoms
is she exhibiting,
and most likely my
diagnosis would be?
Okay.
03:09
So she has myasthenia gravis.
03:11
She felt great when she woke up.
03:13
Her eyelids at first were affected
because eyelids are what’s known as
your type 2 muscle fibers, fast-twitch,
and those are the ones
that are affected first.
03:24
And then eventually,
all the other muscles will be affected to
the point where everything gets fatigued.
03:30
That’s because type 2 hypersensitivity,
myasthenia gravis, destroying
the acetylcholine receptors.
03:38
Keep in mind that if you were to remove
the thymus in this patient, of the lady,
then you might be seeing on
chest x-ray a thymic shadow.
03:47
So either will give you a thymoma or
that’ll give you a thymic shadow.
03:54
Clinical features:
Acquired hypogammaglobulinemia.
03:58
In other words, what’s happening
here is the fact that with thymoma,
it will then have decreased proper
immunoglobulin or decreased immune status.
04:09
Oftentimes, with thymoma, almost always
associated with autoimmune disorders.
04:15
I discussed one with you,
which was myasthenia gravis.
04:18
Is that the only one?
No.
04:20
But a common one, yes.
04:23
But autoimmune diseases should come
into mind or should be highly suspected
if you’re finding an adult who
has a thymus that’s enlarged.
04:30
Remember, we’re dealing
with the thymus here.
04:33
The autoimmune disorders that you’re
paying attention to, myasthenia gravis.
04:37
We’ve talked about this in immunology.
04:39
Just to make sure we’re clear,
a type II hypersensivity,
but this time, we’re destroying
the acetylcholine receptors
at the neuromuscular junction.
04:48
So therefore, what’s actually
happening is the fact that, remember,
you have a test called edrophonium or
the Tensilon test, using edrophonium,
a short-acting
acetylcholinesterase inhibitor.
04:59
And therefore, upon such administration,
you’d find improvement
of her skeletal muscle.
05:06
Another autoimmune disorder
called Good’s syndrome,
which is going to be a thymoma
plus a combined immunodeficiency
and hypergammaglobunemia,
Good’s syndrome.
05:18
Or with a thymoma,
another autoimmune disorder you
might be thinking about is called
complete, complete absence of an RBC or the
RBC population is severely compromised.
05:31
This is called pure red cell aplasia.
05:35
That means that the
platelets are unaffected
and also, you would have unaffected WBCs,
but the RBCs will be purely affected.
05:43
Thymomas, autoimmune associations.
05:47
Myasthenia, Good’s,
pure red cell aplasia.
05:51
Others:
You’ve heard of Grave’s,
pernicious anemia,
dermatomyositis,
and Cushing’s syndrome.
05:59
It could also be associated
but they would give you other
signs and symptoms, obviously,
in which you would know quickly that you
have Grave’s and pernicious anemia,
B12, and megaloblastic anemia,
increased risk of cancer.
06:11
You know about your pH in
your stomach being increased,
all the things we’ve talked
about in hematology.
06:17
Dermatomyositis, you’re paying
attention to the first manifestation,
which would be the skin, derm,
then followed by the skeletal muscle,
also associated with thymomas,
and Cushing’s perhaps.
06:29
Autoimmune.