Tumors of the CNS: Introduction

00:01 Here, we’ll take a look at tumors of the CNS.

00:03 Let’s begin.

00:06 Remember, whenever you find or if you suspect a space occupying lesion in your brain, it could be many issues.

00:14 One of them could be tumors.

00:17 When it is tumors though it is metastasis by far which is much more common than primary.

00:24 But that would be for most organs.

00:27 Metastatic disease outnumbers your primary malignancy of the brain by 5:1 or greater than 5:1 type of ratio.

00:35 That for the most part is true for most organs in the body as we have seen.

00:41 Most common parenchymal metastasis are the lung, the breast, melanoma, and renal cell carcinoma.

00:49 Once again, if you are referring to metastasis to the brain parenchym, then you must know lung and breast, put those together because of the vicinity.

01:03 And then you have melanoma and renal cell carcinoma, which may metastasize to the brain.

01:10 Leptomeningeal metastases can occur from leukemia and lymphoma as well as from breast, melanoma and also your lung cancer.

01:19 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.

01:30 But in addition to that, please know that your parenchymal metastases could also be included here.

01:38 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.

01:47 There is no “characteristic” headache indicating the tumor.

01:51 It could be dull.

01:52 It could be rather intense.

01:55 Incidence of seizures varies depending on the type of tumor and the location, obviously.

02:02 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.

02:17 Our topic at first, apart from metastases, now we’ll begin our official primary CNS tumors.

02:25 Most common tumor type, we’ll talk about age groups, children and adults.

02:32 Now for this, a primary CNS tumor in a child, then we have infratentorial tumors, are more common as our primary CNS neoplasms.

02:42 In adults, it’s supratentorial, are more common as our metastatic lesions as well.

02:50 So you want to know commonly where you would have locations of your CNS tumors, either your population being children or adults.

02:58 Neuronal tumors are rare.

03:01 And neurons usually do not divide after birth.

03:04 And for the most part, you must think of this as being for your boards as being very, very, almost permanent type of cells.

03:12 Now, obviously, research is showing us that maybe perhaps division is possible, after birth, but as far as you're concerned right now, division in these cells tend to be permanent in nature.

03:25 Imaging at contrast, is the best radiologic study to evaluate to CNS tumors.

03:30 Here's an important slide so that you can actually organize your thoughts for primary CNS tumors and begin with neuroepithelial tumors.

03:39 And this will be an important category.

03:41 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 will walk through an astrocytic tumor.

03:55 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.

04:05 In addition, our next classification under neuroepithelial will be oligodendrogliomas, or oligodendroglial tumors.

04:16 And obviously, you know that oligodendroglial cells are your CNS cells or manufacturing plant for myelin in the CNS.

04:26 Ependymal tumors, think about ependymal, and what that means to you.

04:30 And these cells are quite a bit responsible for production of CSF and such.

04:37 Choroid-plexus tumors so both of these you kind of grouped together in terms of where you can expect to see it.

04:43 So these will be important in terms of location.

04:46 And then embryonal tumors, and these tend to be medulloblastomas.

04:50 And that would be an incredibly important brain tumor of a child medulloblastoma, and walk through many of these in great detail.

04:59 I want you to now move in to the meningeal.

05:02 And in the meningeal region we have meningeal tumors and specifically the meningioma.

05:07 Now, keep your parenchyma of the brain separate please from the meninges.

05:11 So imagine now that you have a primary CNS tumor that's developing in the meninges.

05:16 Wow. 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.

05:29 Any if have a hemangioblastoma, and these are important as well.

05:33 And the reason for that you'll see soon enough, is that associations, including with Von Hippel-Lindau disease, A primary CNS lymphomas as well.

05:44 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.

05:55 Then you have a classification of germ-cell tumors.

05:58 A germinoma, choriocarcinoma, teratoma are possibilities.

06:02 Sellar region type of tumors and these include your pituitary adenomas, your craniopharyngioma in a child, notably, and even perhaps a pinealoblastoma.

06:15 So here you have it, in terms of organization of your thoughts, in terms of locations, and under these subtypes.

06:21 And even under these we have our super subtypes.

06:25 And we'll get into details of these.

06:27 And I will point out which ones that you want to pay attention to and give you clinical pearls, as to which, what kind of symptoms and signs that you're looking for in your patient?