Here, we’ll take a look
at tumors of the CNS.
whenever you find or if you suspect a
space occupying lesion in your brain,
it could be many issues.
One of them could be tumors.
When it is tumors though it
is metastasis by far which is
much more common than primary.
But that would be
for most organs.
Metastatic disease outnumbers your
primary malignancy of the brain
by 5:1 or greater than
5:1 type of ratio.
That for the most part is true for most
organs in the body as we have seen.
Most common parenchymal
the lung, the breast, melanoma,
and renal cell carcinoma.
if you are referring to metastasis to the
then you must know lung and breast,
put those together
because of the vicinity.
And then you have melanoma
and renal cell carcinoma,
which may metastasize
to the brain.
Leptomeningeal metastases can
occur from leukemia and lymphoma
as well as from breast, melanoma
and also your lung cancer.
So once again,
if we talk about leptomeningeal
type of metastasis,
here for the most part,
you’re thinking about your WBC type of
pathology, either leukemia or lymphoma.
But in addition to that, please know
that your parenchymal metastases
could also be included here.
The most common presentation as
you can imagine would be headache
and new onset seizures because you have
a space-occupying lesion in the brain.
There is no “characteristic”
headache indicating the tumor.
It could be dull.
It could be rather intense.
Incidence of seizures varies
depending on the type of tumor
and the location, obviously.
Increased intracranial pressure, ICP,
and focal neurologic deficit can
also be seen at presentation,
but not at most times,
but could be a part of the syndrome
of presentations that you’d
be seeing with CNS tumors.
Our topic at first,
apart from metastases,
now we’ll begin our official
primary CNS tumors.
Most common tumor type,
we’ll talk about age groups,
children and adults.
Now for this, a primary
CNS tumor in a child,
then we have infratentorial tumors, are
more common as our primary CNS neoplasms.
In adults, it’s supratentorial, are more
common as our metastatic lesions as well.
So you want to know commonly where you
would have locations of your CNS tumors,
either your population
being children or adults.
Neuronal tumors are rare and neurons
usually do not divide after birth.
And for the most part, you
must think of this as being –
for your boards – as being very,
very almost permanent type of cells.
Now, obviously research is showing us
that maybe perhaps division is possible
But as far as you’re
concerned, right now,
division in these cells tend
to be permanent in nature.
Imaging with contrast is the best
radiologic study to evaluate CNS tumors.
Now, once again,
please be careful here
because if you’re referring to
increased intracranial pressure.
And if there was some kind of bleeding
that’s taking place in the brain,
then obviously, the contrast
here will be contraindicated.
But with tumors,
the contrast would be a very good idea
for you to identify the tumor itself.
Here’s an important slide
so that you can actually
organize your thoughts
for primary CNS tumors
and begin with neuroepithelial tumors
and this will be an important category.
Under neuroepithelial tumor, we’ll
take a look at astrocytic tumors
and then we will further
divide astrocytic tumors
and it is extremely important that you
pay attention to the different grades
that we’ll walk through
in astrocytic tumors
because one of the most common
brain tumors that we’ll find
includes glioblastoma multiforme, which
will be in this category as we shall see.
In addition, our next classification
under neuroepithelial will be
And obviously you know that
oligodendroglial cells are your CNS cells
or manufacturing plant
for myelin in the CNS.
Think about ependymal and
what that means to you.
And these cells are quite a bit responsible
for production of CSF and such.
So both of these, you kind of
grouped together in terms of
where you can expect to see it.
So these will be important
in terms of location.
And then embryonal tumors and
these tend to be medulloblastomas
and that would be an incredibly important
brain tumor of a child, medulloblastoma.
We’ll walk through many of
these in greater detail.
I want you to now move
into the meningeal.
And in the meningeal region,
we have meningeal tumors
Now, keep your parenchyma of the brain
separate, please, from the meninges.
So imagine now that you have a primary CNS
tumor that’s developing in the meninges.
Well, that takes a little bit of time in
terms of developing and as it gets bigger,
what is it going to do?
Well, it may then start invading and
impinging upon the brain parenchyma.
And you have hemangioblastomas
and these are important as well.
And the reason for that,
you’ll see soon enough,
is that the associations including
von Hippel-Lindau disease.
You have primary CNS
lymphomas as well.
And especially if you have a
patient that may have HIV,
unfortunately, there’s a possibility of a
lymphoma developing as a primary CNS tumor.
And you have a classification
of germ cell tumors.
teratoma are possibilities.
Sellar region type of tumors and these
include your pituitary adenomas,
your craniopharyngioma in a child notably
and even perhaps a
So here you have it in terms of organization
of your thoughts in terms of locations
and under these are subtypes and even
under these, we have our supersubtypes.
And we’ll get into
details of these
and I will point out which ones
that you want to pay attention to
and give you clinical pearls as to
what kind of symptoms and signs
that you’re looking
for in your patient.