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Current time:0:00Total duration:10:34

Video transcript

this is Sal and I'm still at Stanford Medical School with dr. Connolly hey Sal we're going to continue going you're gonna have to get one unit of credit for today Oh excellent my mother would be proud so what we're going to look at today is a colon polyp we had said before polyp is something that's gonna stick up like this so that in that last video what we saw it wasn't it was not a polyp that was like an irritant and irritated part of the yeah it was it was very it was very low-lying it was um let me get a pen here we go so the it was really just kind of a patch of irritant right there I see so we've got a bigger piece now I see that's why I just looks okay everything else worsen so you can see the glands look tiny in here but roughly that last slide how big would it be on this thing it would be about a piece like that I'm done to be fair it probably what was that was what was underlying this area right here I see I see and then it grew on to be on something more than that it wasn't this exact one no it was it would grow on to be something like it could broaden so this is something where when we have a colon resection if there's a cancer often there's a polyp or are there an area of that patch like right hyper but not necessarily the cancer is it's in that same section of : yeah we find that people if they have a colon cancer often they have lots of other pre-cancers I see those right just through their bowels is going through a lot like a lot of promise some of its familial susceptibility but a lot of it is that they are showing a propensity to this Isis I don't know if it's from environmental exposures or what I see I just just to remind myself on what we're doing here so you cut out a bit of : that's kind of you can just kind of viewed as a tube because there were some cancer there right and then this thing might be some other polyp that's sitting in that same section that you cut out yeah maybe that first that second slide we saw over the irritation that could be like right there I see as a matter of fact it's important on that you normally wouldn't see this slide in a patient because almost all polyps on the colonoscopy is coming in and they remove it I see through the colonoscope I see because they don't know whether cancer sir I don't know it's not they'll remove it but you wouldn't see the full wall so right out here I mean that's all the way through the wall in which you've got muscle here that's much good part of the wall and so this is the you know really kind of going down to a full piece of the wall I see Wow so so this is a larger piece and this is in order to show the polyp in its natural environment so um so we're going to do is were going to begin looking at the the polyp here and so we will first start way out here which is to go back again to the the normal architecture right right so we had said they're supposed to be tubes luckily this one it's cut right down the middle of the tube so you can see how big the hole is right and so yeah this is normal architecture there and then if I just go out a little bit and I'm just going to come along you can see that you have an area here which there's a bit of irritation so it's a throne up a little bit like we saw before but the real trouble is this thing sticking out right and we wonder what is that thing sticking out and so for the medical students we try to tell them to think like the way the pathologist would be that you first need to look at the overall architecture right this is an abnormal architecture I don't usually stop sticking out then the next thing you're going to do in 3d would look like a mushroom um yeah okay so look like a mushroom actually they tend to have foldings on the top of them so a little more like cauliflower oh I see is it going to be cauliflower classy so then when you look here at color ^ yeah they don't have much color to them in fact the the colonoscopy when they look at Apollo I can kind of tell if there's a chance of cancer because they begin having weird blood vessels I see and just to be clear so that they're not this purplish color that worse you know this is a little color added then section and we had to put this it would be colorless otherwise so we had to put a stain right right around they see them so now what I'm gonna do is I'm going to draw the area we're gonna do a comparison see this thingamabob here yeah oh you're gonna look at that so now miracles of science yeah it's a cardiology so I'm so these are cells which are relatively normal these are cells which are abnormal and when we look at them a pathologist immediately says these look angry they do they don't look at I would say that too and so when you look so what's angry about it as first of all they're not committed to being to behaving proper behavior over here nuclei belong at the bottom right the things that you're supposed to do for your job Jo B where are at the top yes and so when you look at these guys it's like where's your job yes and so a few of them are making mucin but these ones have nuclei of different sizes and shapes yeah and they're all just they're just doing their and they're not even doing muse in there no some make museum a lot of all they're doing is growing right and so usually there's a playoff between that if you're committed to your specific job for writing we call it differentiation right if you're committed to your differentiation you tend not to have as much propensity to grow yeah and if you tend to grow a lot yes and not to do the differentiation and so this is largely that you have this sort of chaos of nuclei less commitment to the normal structures right and you're not producing as much and so what this is is this is now called dysplasia dysplasia dys alright later than the wrong so yes the wrong right right and so that's what we're just saying is we don't like the looks of these ones and so these individual cells look dysplastic and they grow so then to tell whether it's cancer cancer means in this organ that you've grown across this line in the sand so let me clean so literally so if you've crossed this boundary right over here cancer right so you so even if I'm in the polyp up here and I'm controlling uncontrollably you know cancer cells and it's mutated and it's not killing itself with what right supposed to you still would not call it so actually cancer no so what happens is that there's a middle term right where it's a cancer in the still in the usual place right and that's carcinoma in situ did you see okay so carcinoma in situ means it's not an invasive cancer and therefore most people would not really call it a cancer it's just so wild looking up here right you know that it would do that if it has given any chance or time I see so what we're saying is if something was out here a carcinoma in in situ yep yeah that eventually probably would make its way yeah it just looks so keep committed to growth and so aggressive and right so little differentiation but you know if you gave a time you'd worry that it make sense so with here though this is dysplasia where it's it's very upsetting that it's growing so fast what's important about this right is in hyperplasia right if you took away the stimulus or irritant right you would go back to normal yes this will not IC like we said like this are some irritants in the last video is like a week later we had a couple weeks later that that hyper pleasure would go away right this pleasure is here to stay that's right this is and so the key word we use is autonomous automatons independent it's just whatever so it will grow no matter what it doesn't care about clues from neighboring cells right doesn't need something driving it so what you have then is this is growing right and if it's growing and it's all by itself and growing its then called a neoplasia your last fascia right so neoplasia showing displays so yeah so dysplasia just is more of when you go and to look at these guys these features I was like this particular feature these cells aren't growing right I said so that's an example of dysplasia right that's dysplasia and then overall this lump right is a new growth new growth it's a neoplasia right and we you reserved it in the medical field for me it's growing on its own and how do we know it's new because as you said it sticks around yeah like the hyperplasia so so how'd you know this wasn't around for like a year oh it probably was so I think it actually came from an area here and the thinking would be that you probably had irritants or hyperplasia right it would continue to grow cells divide so as to buy too much and then one of them made a mistake I see and so then it then clicked on something where it would say you know what from now on I'm not listening to any clues a cup worker and then all of its descendants were crazy - that's right so then it would then have a real mean streak yes and so then they would grow from here so this is an area where you can see I see that pattern in my own family yeah exactly so then here these are more normal glands but even these yes that's dysplasia right right so these are growing and they do not have a good pattern of growth right overall this lump right is a neoplasia I see I see so when we say new it's kind of newer than the other tissue oh yeah we don't really need so much the new or meaning that's new in the others as much as its its own thing I see no new kid on the block okay okay so so this is the Nia place I see I see all right so this one here is a polyp um it has features of dysplasia right but we would say we see no cancer I see how would you know that and so um and I write because it never co-found real and this is there's a reason why the boundary is important is that if you look here these are all the surface cells um down here that these are the vessels that go to the rest of the body right is these are blood vessels right these ones are called lymphatics and what lymphatics are is they just take the clear fluid right around there so so these these right here these are the emphatic stew clear fluid right and there is a fluid can go back and forth between blood vessels and the lymph system yeah usually what happens is that um blood comes in an artery like this right goes on down to these little vessels and then a little bit of the clear parts of it right will kind of leak out it like that the red blood cells are too big yeah Kelsey and right right so then the lymph is the clear stuff that comes out and then this is how it gets back to the rest your body or through these lymphatic so you can see you do not want neoplastic cells in right because once in there neither they can they can get to any part of the body so any place and then guess what set up shop New Kids on the Block they just do with the Isthmus die I can't say the word miss Costas metastases metastasis so metastasis would be if it gets into these things right I can get out of the colon when you're in a variety so so this is one where it is not cancer and it has not invaded these areas where it gets to the rest of the body fascinating fascinating