[Music] okay everything looks good on your end looks good on my end all right sorry about that guys we'll catch up here so appreciate the introduction uh again i'm corey there on my first slide is my email and my cell phone and i encourage you guys and gals out there to jot that down and feel free to contact me directly if there's anything i can help with with this lecture or uh in neurosurgery in general i'm very happy to to help with any anything out there as you're thinking about this career so um this uh seminar tonight is on this very large topic of gliomas of course there are lots of other brain tumors out there that we uh treat uh but this will focus on gliomas and and of course within this topic of gliomas this is an enormous uh area to talk about so there's a lot of things that we could go into what i'm going to try to do is give sort of an overview of things that i think would be of most interest to you and then just to remind you next week uh we will dive into this further and we'll go through a few cases and that will really dive into what treatment is like for these gliomas again i encourage you guys to use that q a box to add your questions and at the end i'll do my best to go through those uh in the time that's that we have left okay so here's a list of objectives this does not exactly match the objectives listed on the website for the training center but i think it is still going to be a comprehensive uh coverage of this topic so let's get a definition out there to for diving into this so gliomas are the most prevalent primary intrinsic tumors of the brain and spinal cord histologically they share characteristics of normal glial cells so we're talking about cells like astrocytes and oligodendroglia however rather gliomas originate from normal glial cells glial or neural precursors or stem cells or other cell types still remains a topic of investigation if you just quickly google glioma mri you're going to quickly get a sense of the diversity of tumors that are out there so the way they present clinically the way they look radiographically and of course the types of glioma is incredibly diverse so that's why we have a lot of uh colleagues out there who who really focus just on gliomas and in our truly glioma surgeons because it does take a lot of focus and expertise to to handle this category of tumors so what are the possible gliomas i think the best way to kind of define them is to look at the world health organization's classification scheme and i just want to point out that in 2016 there was an update for that classification and that was updated from about 10 years ago and you can see the red editions here with lots of changes and if you just kind of step back you'll see that in red the most common things are genetic mutations so for the very first time we are now using genomic data to to really define uh meaning gliomas so uh very quickly let me just skim through this list here so on the left here are the diffuse astrocytic and oligodendroglioma tumors so diffuse astrocytomas and a plastic astrocytomas glioblastomas and you'll see therefore further subdivided into idh mutations and wild type we'll talk more about that later there are a few uh sort of oddities under glioblastoma which are uh refer to their histology moving down the list there's this unusual uh diffuse midline glioma in the younger population that has commonly has this specific mutation kh i'm sorry h3k27m here's your oligodendrogliomas and they can be defined by idh mutations and 1p19q chromosomal deletions of course there are anaplastic versions of that there are these mixed versions moving over to the right here are some more astrocytic or glioma tumors like the polycytic astrocytomas of epidemiology giant cell astrocytomas plutomorphics xanthe astrocytomas epinemal tumors are on this list we're not going to talk about those uh but just keep that in mind there there they are other uh gliomas in include these cordoid gliomas and a few other odd ones and then there's a list of mixed neuronal and glial tumors so the bulk of these gliomas are here on the left and that's really what we'll focus on just for this lecture so that classification scheme uh defines those tumors as we were just going through but then defines their who grades and so the grading system is important to to think about so there's grades one two three and four that you've heard before and just to quickly remind you so grade ones these are tumors that have low proliferative potential uh very discreet on mris and in the brain and possibility of curing them just simply with good surgical resection grade two tumors uh have more atypical cells more infiltrating nature but still have a low mitotic activity they do recur more frequently than grade 1 tumors some of these grade 2 tumors can progress to higher grades of malignancy grade three tumors so this is where we start to see histological evidence of malignancy such as nuclear atypia anaplasia increased mitosis much more infiltrative capacity so these tumors require uh post operative aggressive adjuvant therapies like radiotherapy and chemotherapy and then of course the very common grade four these are the most mitotically active have necrosis have a lot of neovascularity very infiltrative rapidly progressive and require aggressive treatment and universally fatal so all of those gliomas that we just went through on the prior slide can be graded one through four and that's very important to help with prognosis and uh with thinking about appropriate therapies i threw in this slide because i thought this was a good illustration of something uh from this classification scheme so as i was telling you all these gliomas can be classified by the specific type of glioma and then by the the who grade system but it's not a perfect system so for example some of these tumors uh correlate very very well with what you would expect from the grade that they're placed in so the way they represented here on this picture is there's a very clear line demarcating the green color from the orange color so tumors that are correctly diagnosed and put in this category clearly behave like grade 1 tumors so we have a good classification scheme for these tumors if you go to the right over here you can see that there's a blending of the color and so what they're trying to suggest is uh we our classification of these tumors uh is is poor there's a poor correlation between what we are calling these tumors in their in their behavior so in other words uh we need a lot more work out there so that's another reason why i'm throwing it out there to you guys is if you're looking for areas to explore research these tumors need better classification schemes so that we can place them in the proper grading system uh to help with prognosis but of course that further study will lead to understanding those tumors better and better therapeutics [Music] hey everyone ryan rad here from 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