00:01
In this lecture,
we're going to talk about gliomas,
or that most common type
of malignant brain tumor.
00:08
We're going to follow
a patient's course
through diagnosis
and treatment,
and learn about how we both approach
patients in clinical vignettes
for this common and complex
type of brain tumor.
00:20
Let's start with a case.
00:22
This is a 49-year-old man
who presented with headache.
00:25
He presented with six month history
of cognitive complaints,
which culminated
in persistent dull headaches,
and intermittent episodes
of word-finding difficulty,
possible seizure.
00:37
After presenting to the
emergency department
with an episode of
more prolonged aphasia,
a CT scan showed left brain lesions
or a left brain lesion.
00:46
and he was admitted to the hospital
for MRI of the brain
with and without
gadolinium contrast.
00:52
Ultimately, the MRI showed
a non-enhancing lesion
in the left temporal lobe.
00:57
So what's the diagnosis?
Well, let's think about
some of the features of this case.
01:02
First of all, this patient presents
with headache
and some type of
paroxysmal episode.
01:08
When we think about
paroxysmal episodes,
episodes that have
the same thing every single time,
make us concern for a seizure.
01:16
And this sounds concerning
for a seizure.
01:19
The second is the imaging.
We have a parenchyma lesion,
a lesion that appears to be
inside the brain,
where we think about the cell types
that are in the brain
in terms of an imaging differential,
and this is a
non-enhancing lesion,
suggesting that
it may be lower-grade,
which is consistent with the
six month history of presentation.
01:38
Here's the imaging for this patient.
01:40
And we're looking at
two types of scans here.
01:43
On the left, we see a T2 image
that shows us swelling and gliosis
anything that's abnormal
around this lesion.
01:50
And on the right we see
a T1 post-contrast image
with gadolinium in the veins
but not in this lesion.
01:58
This is a non-enhancing lesion.
02:00
So in summary,
this is a lesion
in the left temporal lobe
without enhancement.
02:05
And this makes us concerned
for a low-grade lesion,
a low-grade tumor.
02:12
So what's the diagnosis?
Is this a brain metastasis,
a meningioma,
a pituitary adenomas, a glioma,
or a vestibular schwannoma?
Brain metastasis
could be the case
but this patient's history
is quite long
and no systemic malignancy
to suggest a clinical history
suggestive or consistent
with brain metastasis.
02:32
The patient doesn't present with
symptoms of a vestibular schwannoma
and imaging
is not consistent with that.
02:38
The lesion is not in the pituitary
or the sella turcica,
to suggest a pituitary adenoma.
02:44
This lesion looks to be
inside the brain
as opposed to developing
from the dural surface.
02:49
And imaging would be inconsistent
with a dural base lesion
like a meningioma.
02:53
This is a glioma.
02:55
And this is the typical
a classic presentation
for a patient with
a low-grade glioma.
03:01
Let's take a different case.
03:03
The same 49-year-old man,
but this gentleman presents
with a one-month history
of cognitive complaints,
a shorter time course
of presentation
that culminated in severe headaches,
gait dysfunction and falls
and right-sided weakness.
03:18
We don't see a history
suggestive of seizure.
03:21
This patient has a
focal neurologic deficit,
suggesting that this lesion,
this mass,
maybe this tumor
is growing more rapidly.
03:28
Again, after presenting to the
emergency department,
a CT scan shows
multi-focal brain lesions
and he's admitted the hospital
for an MRI,
which shows a ring-enhancing mass
involving the corpus callosum.
03:41
So again, the time course is
suggestive of more rapid growth.
03:45
We see focal neurologic deficits,
which means this
patient needs imaging.
03:49
And on imaging,
we see a ring-enhancing lesion,
which could conjure up
an important differential diagnosis
for this patient.
03:56
Let's look at this
patient's imaging.
03:58
Here again, we're looking at T1
post-contrast imaging on the left,
and on the right,
the T2 imaging
showing this area
of edema or swelling,
abnormal finding
around this tumor.
04:10
This enhancement pattern,
the ring of enhancement
is concerning for a
higher-grade lesion,
and a possible tumor.
04:18
So what's the tumor?
Is this a brain metastasis,
a lymphoma,
a low-grade glioma,
a high-grade glioma?
Or could this be
multiple sclerosis?
Well, low-grade glioma,
we just saw what that looks like.
04:30
and that's typically a nonenhancing
or tumor without enhancement,
and this one
prominently enhances.
04:36
We don't like low-grade glioma.
04:38
Could it be a brain metastasis?
It could be,
but we've seen
in brain metastases
that those tumors
like the gray-white junction,
that area between
the cortical gray matter
and the
subcortical white matter.
04:50
This lesion is in the
white matter.
04:51
It's along the corpus callosum,
the white matter tracks
and actually has a
butterfly appearance
spreading and emanating
from the corpus callosum.
05:00
Could this be lymphoma?
It could be.
Lymphomas can look tricky.
05:04
But typically lymphomas
are homogeneously enhancing.
05:07
And this has a
ring-enhancing pattern
that really favors
an alternative diagnosis.
05:13
What about inflammation?
Could this be multiple sclerosis?
There's this a
type of multiple sclerosis
that can cause
a tumor like lesion
it's called tumefactive MS
or tumefactive multiple sclerosis
but typically
inflammatory lesions
don't have a complete ring
of enhancement.
05:30
There's an incomplete ring
of enhancement.
05:32
And so here the imaging features
in clinical presentation
favor a high-grade glioma
or glioblastoma.