so this videos on brain tumors and unfortunately there's a lot of information that is fair game as it when it comes to brain tumors but fortunately for you if you organize it with some sexy dirty USMLE mnemonics it's really not that hard this is gonna be free points for you on test day and it's a huge section of Neurology anybody who's flipped through first aid knows that neurology is a very very long section lots of information that you need to know but we're gonna simplify it for your studying pleasure so in this video we're gonna talk about brain tumors when we talk about brain tumors you need to separate them into the tumors of adulthood or the tumors of childhood and I've done that for you here tumors of adulthood include glioblastoma multiforme a oligodendrocyte OA tarry adenoma and schwannomas children tend to get different tumors and they include pilocytic astrocytoma medulloblastoma ependymoma and craniopharyngioma and pinny Aloma pineal OMA that's a hard one to say we're gonna start by talking about the tumors of adulthood so we're gonna focus on the left side of this chart as I go through the video today we're gonna talk about just in general what you need to know about the tumors what you'll see on histology and then I'll wrap up by giving you the mnemonics after we cover all the adult tumors we'll transition into the tumors of childhood and we're gonna just simplify everything I'm really excited to share with you this video because it's very very high yield so this is a slide that you'll see on most of these tumors again we're gonna talk about what you need to know just generally speaking what you'll see on histology and then I'll give you my favorite mnemonic so we're gonna get started with glioblastoma multiforme a so this is our first tumor of adulthood and what you need to know in general are that these are highly malignant tumors so they're very aggressive very invasive highly highly malignant and they tend to cross the corpus callosum so they'll cross the midline when you see them on radiology and this is pretty unique to this tumor so I'm gonna show you the picture on the next slide but if you see that it's pretty classically glioblastoma multiforme a on histology you'll see something referred to as quote pseudo pallas ating tumor cells and these stain positive for GF AP or G fab so here's what a glioblastoma multiforme it looks like and as you can see if you know where the corpus callosum is which hopefully by this point in your career you do this tumor crosses the midline and it creates what's called the butterfly appearance because it's sort of symmetrical on both sides of the corpus callosum so glioblastoma multiforme a if you see anything resembling a butterfly or anything crossing the midline in the brain it's gonna be a GBM so if we come back to GBM my pneumonic is glioblastoma multiforme a so he just changed the B to a P and what does that tell us well g4g fat positive P for pseudo Pallas ating cells and M for both midline and malignant so we're gonna keep it stupid simple here GBM glioblastoma multiforme a I say glioblastoma multiforme AGP m4g fab pseudo Pallas ating and midline malignant that is your glioblastoma multiforme a so we're already one tumor done you need to know everything that I said but if you use the pneumonic it beautifully summarizes all the high-yield buzzwords for you so if you see any mention of that stuff on exam day you know that it's a glioblastoma multiforme a so don't get bogged down dirty us emily is gonna keep this simple our next tumor is the oligodendrocyte on G so you see things that are known as chicken-wire capillary patterns you see fried egg cells and you see these tumors tend to be calcified grossly so this is really a big one for just histology there's no general knowledge that I think is high-yield for us Emily or complex the reason that they're called fried egg cells is because they have these classic round nuclei with clear cytoplasm and it's sort of like if you fry an egg you see that the yolk is very clear you know clearly defined but it's surrounded by the clear cytoplasm which would be your egg whites if you were to fry an egg so I don't necessarily agree that this looks like a fried egg but that's what pathologists and histology is call it so that's what we go with the round nuclei clear cytoplasm those are termed fried egg cells so if you haven't guessed yet our mnemonic is gonna be Oleg oh dendro glioma because all of these buzzwords have something to do with eggs so the chicken-wire capillary pattern well chickens lay eggs the fried egg appearance that's a No and you get your calcium if you eat you know a nice hearty breakfast with eggs so calcified tumors Oh Lego dendro glioma instead of oligodendrocytes all you need to know for a Lego dendro glioma so if you're cool it's that you already know two tumors we're crushing cruising our way through this list let's keep the momentum going so we're gonna talk about meningiomas next so meningioma are benign and they tend to be superficially located because they occur on the meninges and if you think about the anatomy of the brain the meninges / lie the superficial aspect of the brain so it's no surprise that a tumor that originally arises from the meninges will be superficially located these are arachnoid in origin and think about the arachnoid mater in order to make the connection between their origin and the fact that it is a meningioma so it's a tumor of the meninges on histology you'll see similar bodies and spindle cells and I'm going to show you on this slide what this all looks like so you can see at the top portion of these slides on CT scan we see that the tumors are very superficially located because again they're extensions of the meninges so meningioma meninges is in the name you can see at the bottom of this slide I'm showing you what a Sumomo body looks like so some omma bodies are unique to just a few tumors in the body and meningioma czar one of them now how do we remember all this right dirty' us Emily what is your sexy sexy mnemonic for keeping this simple in my brain well you need to say men have problems with PSA so men for meningioma the first three letters of the tumor and men have problems with elevations in PSA because when they get BPH they have an increase in their prostate specific antigen so that's what PSA stands for if you haven't heard about that yet you certainly will as you move forward in your career but men have problems with their PSA so a PSA is our pneumonic so pee for Sumomo bodies s for spindle cells an a4 arachnoid origin if you can remember those three facts about a meningioma that's everything that you really need to know or at least that's everything that's very high yield if they ask you a question about meningioma x' that's not one of these three things not p naught s not a then it's not worth the brain space to memorize but that's what we do here at dirty USMLE guys we keep this stupid we keep this simple three tumors down some more to go let's keep it rolling hemangioblastoma probably one of the easier tumors to remember so this is of blood vessel origin it's an eco producing tumor so it can cause secondary polycythemia it's associated with von hippel-lindau syndrome very very high yield to know that and on histology you'll see thin walled capillaries so no surprise the mnemonic we're just breaking down the word for you oftentimes if you're confused on us Emily comlex or even your in-class exams all you need to do is look at the word to figure out what it had you know like what the answer is so hemangioblastoma so heme for blood angio angio means blood vessel and blastoma is sort of describing the appearance grossly of the tumor so heme for blood so these are eco producing tumors they're for blood eeep oh you know eople causes polycythemia so that's a disorder of blood so heme angio means blood vessels so these are of blood vessel origins and literally when you look at the histology you see thin walled capillaries and then black stoma is irrelevant so we're just breaking down the word to help remember this one sometimes it's not worth memorizing a mnemonic heme angio blastoma blood blood vessel blastoma and then just to take it one step further to remember the association with von hippel-lindau syndrome sometimes instead of saying von hippel-lindau I say von eople endo because it's sort of the same pronunciation that reminds me that not only are Heba angio blastoma associated with von hippel-lindau syndrome but they're also associated with Ipoh and they cause secondary polycythemia so keep that stuff in mind very very high yield associations hemangioblastoma we're gonna talk about pituitary adenoma sneck stand this is probably the highest yield tumor on this entire slide in this entire section so let's get right into it with pituitary adenoma so you can have one of three forms of the tumor so it can be a lactate Rauf a Samana troph or a non-functional pituitary adenomas so what the hell do these words mean relax better break this down lacta troughs refer to one type of pituitary adenoma and specifically it's a pituitary adenoma that perdu is prolactin hence the name prolactin oma so in a prolactin oma which is just a subtype of pituitary adenomas which is termed electa trophic pituitary adenomas aka a prolactin oma it produces prolactin and because of the inverse relationship between prolactin and FSH any increase in prolactin will decrease your FSH which will manifest as a certain very classic set of symptoms so what does elevated prolactin cause and likewise what does decreased FSH cause so in a female you'll get things like Galacta Riya and amenorrhea all right in men however you'll get gynecomastia and decreased libido because you're inappropriately producing elevated levels of prolactin and you're shutting down FSH so these are very classic symptoms that you should be on the lookout for if you see that constellation of symptoms in the clinical vignette chances are it's a pituitary adenoma and the sensitivity for it being a pituitary adenoma becomes even higher if they have other symptoms like headaches etc so that is a pituitary adenoma but a very specific subtype of pituitary adenomas called a prolactin oma now let's talk about the somatotropin pituitary adenoma so the somatic trophic pituitary adenomas could be a tumor that produces one of four substances it could produce growth hormone it could produce TSH it could produce ACTH or it could produce FSH or LH so no surprise here these are all hormones that are secreted by the anterior pituitary okay so when we talk about these hormones if the pituitary adenomas is a somatotropin dit produces growth hormone you're gonna see clinical constellation of symptoms consistent with gigantism or acromegaly likewise if it's a somatotropin do sis TSH you'll see things like hyperthyroidism if it's ACTH ACTH producing you'll see Cushing's syndrome and then FSH LH you'll see the same set of symptoms that you should see if you just understand the physiology behind these hormones so my recommendation before you kind of memorize this and go through this lecture is to understand what these hormones do so go through the endocrine section first because it's extremely high yield to be able to make that connection so if you have a clinical vignette and the patient has tachycardia you know diaphoresis but headache and there's something seen on the CT scan that it sounds like hyperthyroidism but you see this tumor so you got to connect the dots and say this is a matter of trophic pituitary adenomas that's producing TSH so that's how you approach these problems so somatotropin hormones that come from the anterior pituitary and the symptoms are exactly what you would see if you just had elevations in any one of these hormones so not too difficult to understand the non-functional pituitary adenomas don't produce hormones hence the name non functional so what kind of symptoms will you see on test day well you'll see things consistent with Mass Effect and Mass Effect refers to headache and bitemporal hemianopia so the bitemporal hemianopia is the symptom that you get when you compress the optic chiasm and because of the location in the pituitary the pituitary adenomas has a tendency to compress the optic chiasm and caused by temporal hemianopia so right now I want you to pause this video and go on Google and Google bitemporal hemianopia and I want you to see what that changes in the visual fields because if they describe what you see on google images when you google bitemporal hemianopia they're probably hinting at a pituitary adenoma so make sure you understand how the visual field changes if the buzz word is bitemporal hemianopia aka a non-functional pituitary adenoma compressing the optic chiasm and then obviously headache because you have mass effect you have a tumor growing in the brain kind of subtly pushing the brain in a certain direction so that is Mass Effect for a non-functional pituitary adenomas so how the hell do we remember all this stuff that's the question this is really easy eyes remember add Anoma so add Anoma because you're adding on all of these hormones in the brain or you're adding on the actual mass of the tumor to create mass effect so pituitary adenomas x' add hormones into the picture like prolactin GH TSH ACTH FSH LH or they add their mass into the picture to create headache and bitemporal hemianopia very very high-yield tumor to understand I think I simplified it well for you but make sure that you understand everything on this that is pituitary adenomas we're gonna wrap up the adult tumors by talking about the famous schwannoma so the schwannoma gets a lot of love on tests because it has a very classic presentation so it occurs at the cerebellopontine angle so Google that really quickly so you see where that is but when you have a tumor sitting in the cerebellopontine angle it has a tendency to affect cranial nerve seven and Creole nerve eight so your facial nerve and your vestibular cochlear nerve so the thing that you need to know about schwannoma is in addition to which cranial nerves they affect is that if they're bilateral you want to think neurofibromatosis type two so if they're unilateral it's just in a coma existing in isolation but if you have to chew on ouma's right bilateral schwannomas you should think of nf2 that's very very classic Association very very high yield to know that on histology you need to memorize that schwannomas rs.100 positive so if you need a mnemonic you need some dirty USMLE lovin just remember schwa Anoma so the SCH w very very high yield s for s 100 c4 cerebellopontine angle and the h and the w tell you which cranial nerves are affected so the H hearing is affected that's cranial nerve eight and the W winking is affected that's cranial nerves seven so very very high yield schwannoma SCH w just remember what their stand for s 100 cerebellar Ponty and hearing and winking that's cranial nerve seven and cranial nerve eight if you have bilateral schwannomas it's an oral fibromatosis type two very high yield association so that's all of the adult brain tumors those are the hard ones guys so that's done we've covered all the hard stuff you have mnemonics for all the hard stuff the childhood tumors are a lot easier and the reason is is that childhood tumors you just need to know maybe one or two buzzwords associated with each tumor and if you know those buzzwords you are golden you are absolutely golden they don't ask a lot of this on exams so we're just gonna cover the buzzwords so we're gonna do this all in one fell swoop so I'm gonna put through the buzzwords on the right side of the slide and then I'll go through them one at a time and explain how you remember this so the tumors are pilocytic astrocytoma medulloblastoma ependymoma craniopharyngioma and Pinney Aloma okay what you need to remember corresponding to the tumor is exactly a cross right is that in pilocytic astrocytomas you get things called Rosenthal fibers and they stain positive for G fat okay so how do we remember the association between pilocytic astrocytoma and Rosenthal fibers right so random the way that I think about this and you sort of need to be a sports fan to understand my pneumonic here is that there is a sports agent named Drew Rosenhaus so I remember Rosen for Drew Rosenhaus and then in astrocytoma I think of the Houston Astros and even though he's a football agent he represents football players I think of him as representing players who play for the Houston Astros so that is Drew Rosenhaus from rosenthal fibers representing players on the Houston Astros in astrocytoma so very very high yield to know that Association that's my silly sports mnemonic sorry if you're not a sports fan next for medulloblastomas you need to know about Homer right rosettes so what the hell how do we remember this again sorry but you kind of got to be a sports fan for this one if you want to hit a homer run or a home run out of the ballpark you need to blast the ball so you blast the homer run or the homer right rosettes so for Homer right rosettes you blast the homer run out of the ballpark that is the high yield mnemonic for medulloblastoma for ependymoma you get something called perivascular pseudo rosettes so one buzzword to know here perivascular pseudo rosettes so I sort of create a story in my mind and I think about my momma right my mom ependymoma append a momma append a mommy however you want to do it and you forget that it's your mom's birthday so you give her a rose which is pseudo rosette but since it's pseudo rosette its pseudo means sort of or kind of or like somewhat so it's pseudo rosette you you gave your mom a rose to somewhat make up for the fact that you forgot her birthday that's just how I always remembered that it's sort of a stupid story but it absolutely works so if you get a pen demo aka append Amami Penda mama just remember that you sort of forgot her birthday so you gave her a sort of makeup gift which was a sort of rose AKA pseudo rosette so that's ependymoma for craniopharyngioma all you need to memorize is that these are remnants of wrath use pouch that give rise to craniopharyngioma x' so there's no pneumonic there it's just a brute memorization if you see wrath key anywhere on your exam the answer is current craniopharyngioma like don't don't think twice just pick it that's the answer and fourpenny Aloma it causes paranoid syndrome but you remember the peas Pinni Aloma for paranoid syndrome look into what that entails exactly i would google it it's a little lengthy for an explanation in this video but the association itself between pineal Ouma's and paranoid syndrome is extremely extremely high yield so know that association but guys and gals that's it you now know all of the brain tumors that occur in adulthood in childhood there's no reason to go through any other resource and learn anything else about these freaking tumors they're really annoying to learn and if you're not gonna be a neurologist you really don't have to know that much about them just know the buzzwords that I've presented to you in this video remember to check out the description of this video give us a follow on Twitter if you want us to make a video about a certain topic all you got to do is tweet at us and I'll feature your tweet in the next video when I create the video for the topic you requested