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Current time:0:00Total duration:12:37

Video transcript

this is Sol again and this is part four on this series that we're doing at Stanford Medical School with dr. Connelly all right Sal we're back here again this is now the fourth of the slides and this would be now the business for why that segment of colon was removed this is the colon cancer well well so just to orient we'll go now to come to the drawing which is like you're saying before up here this is the this is the lumen right here right on out here that's the lumen is the inside of the inside the right side out here this is the rest of your belly right where the bowel is all kind of rotating around in the abdomen right and so um is there a word for like inter abdominal yeah peritoneal peritoneal is okay the peritoneal cavity is where all the bowel loops are kind of just all right it's moseying around it's okay and then what we have here is this is the important part which is this is the muscle right that allows peri stall psious yes that's the peri I learned that inhale that's the the kind of moving the undulating motion to push stuff yep right it'll go and it'll sort of milk it along and all right just move long right so you can see the muscle looks all fine there that's how thick it's supposed to be and it all looks fine over here so let's go what what scale is this like how thick is that much and so we're now once again our tiny little red blood cells are those little dots there right and so we're talking about the thickness here as a few millimeters that muscle is about if you remember back to this guy that was about six millimeters so it's about that's about six okay okay millimeters thicker that's actually strong right a very very strong muscle and you can kind of see it goes up here it kind of comes around here but it's looking like it's troubled home on this area yes and this this stuff all the stuff this is just this once was probably a polyp and turn into a kind of this massive polyp yeah so we have the normal over here for the lining this is where it's going dysplastic right looking a little bit bad there there's where it's going dysplastic and so now what happens is you've got these edges of dysplasia when people the medical fields say plastic they're saying that word means tissue well plastic and generally plastic surgery or the plastics of as far as a material sign it means moldable I see it also means you can grow with it eyes change shape right so we call something plus it's moldable tissue it's the shape a shape a shape and so the shape changes were wrong I see and actually dysplasia can refer to a cell tissue and organ or an entire limb okay so okay just means it grew wrong Isador molded wrong so now this this is where we have the cell dysplasia this is all the bad stuff right and it basically started probably somewhere up there and is invading right Easter's one one cell up there just started dividing uncontrollably that's right it's exact but it started from one cell being very bad it often though starts and I'm going to change now so we're gonna lose our art okay so what I'm going to do is change is that it often starts though from one of these right meaning maybe a cell went bad right around there right now really is starting it's only say growth it's not just one cell it's all of us descended it's descendants and billions of cells right are growing in order millions and billions are downward Nord right now right in this case grow all the way through well and so you can see the scale yeah is it not only grew a little bit it went right through the muscle yeah Wow okay so going back to this guy here this is now and there are some like that the body does have things to fight this off but it was unsuccessful that's right and so there are certain conditions where if you decrease the immune functions right you'll get cancer I see and so it still argued though whether it's that you immune system is decreased you got a virus and right the virus caused the cancer right or whether it's there's a lot of surveillance right and that holes are no show that viruses got me it's fascinating it's because viruses are messing with are sometimes I mean isn't the significance of our own DNA from ancient viruses and yeah and I think there's a couple big categories is that viruses can get into your DNA where I really screw up the DNA and you know integrated into it but they also like we said before it can lead to irritation alright and we're so growth and have troubles there make sense so now we're back here in which we're looking at the cancer which probably like you said started here and is growing including spreading out all the normal tissue around it Wow and so we're going to look now at the cells so zoom in zoom time hang on to your hat yeah okay so what we're going to do is first probably go into a lower power here is look at the edges of this so once again we find normal right and so this is even not perfectly normal you can see it's a little bit dividing and a little bit irritated right so this is irritated along the edge hyperplasia Jackel exam something alright so so then what we have now is as you go in deeper these are the areas which normal but this is all kind of coming out you know like we're saying up here kind of growing out in all directions this is now where you can see the cancer next to normal you know we've talked before about dysplasia this is really bad right capital d yep small children off the street could be able to tell you that this is bad right and so whenever they watch this video yep exactly okay and so these are the normal ones they're doing their J OB job right making them using nuclear at the bottom what is this guy doing right this is yeah just chaos yeah so before we talked about carcinoma in situ right cancer in spot if you saw cells this bad you'd say do not let them go far ice because they will have a tendency invade they're crazy so this right here is a bunch of the cells that's a bunch of the cells there these guys here you can see they're really haphazard they're growing they're not doing their so if uh if we found a polyp that had this stuff that didn't cross that boundary line yet we still would say no we got to take this you know well I guess we already took it out okay so um so cancer the colon is one of the ones where surgical cure is still classic right cut it out and you're probably in pretty good shape right and so there you'd say well if is a tip of the polyp and look like this I think we got it out but you'd say to yourself we better watch this purse I see so if the whole polyp kind of look like that you're like ah let's cut out a bigger section yeah then you might so if it's going down into the neck or getting a little further or if you cut across it at the margin then watch out but here's the problem is remember how I said up here it's not a big deal but once you get down near the Hawley's and arteries these guys are running amok down by the veins of your so you actually see these kind of these cells have split off yeah so and see these guys here so that's one little nest to sell there's one that's probably right there a cancer cell just dying to get into that little vein right so this is actually I can never say the word metastasis this is it we're seeing it this is where would come from we're starting to happen so these guys are the bad actors they're growing in next to these very fragile little blood vessels and so that guy is knocking on the door right once it gets in here that's a venial meaning a little vein right that's the road out right and it just looks like a circle here because it's a two-dimensional cross-section of it but it should imagine popping in or out of our screen yeah so be pumping in our screen so this guy would kind of go in and out screen connect to this one and then it would go out and it's officially recognize a word metastasize once it's it's found a beachhead someplace else um that's right so it's considered a metastasis where let's say the cell got into the vessel right if it left the region okay so it went to the long I see but the slaver is looking like it this is looking like you really are worried that this could metastasize right and so what's interesting about this is that when you look at something like this there's such a thing called for cancer grade right and what grade is is basically what we've been just talking about how bad does that look right right and so the grade is wow that looks nasty right I think that's nasty a technical term actually we use it quite a bit people say what would that timber show we said it was nasty when we talk about nastiness it's a lack of behavior if you can get a cell where the nucleus gets that big or sometimes it's that big there's chaos right and there's chaos not just a nuclear size but how it behaved I guess the nuclear size is what is a telltale because that means that the cell is devoting a lot of its resources for replication and it's a replication but it also means to me that normally things in the cell are very orderly right you do not divide your DNA until these things are are icy and now it's just doing it and now it's just left and right so so yeah this would be a high-grade tumor Wow and then stage is the other main thing for the stage means where is it in the body right so in this case um if it's these nasty cells at the very top it's actually a lower stage than if they're nasty cells and they've come all the way down here so it's in situ carcinoma would still get a stage it's a stage zero stage zero so it's basically you're nowhere and if you begin to just cross over like here right and Dade then your did a stage one and then their depths as you go for stages and then there's always the other thing where did it go off to other parts of your body right and that's the very highest stage and so this isn't a and this is true of all cancers when people talk about breast cancer I've heard it in that context left stage one stage or stage zero through four and so it isn't just the size so if the if the the cancerous tissue is big but if it's in a safe place it could still be stage 1 or stage it is what's interesting about staging is almost the whole world has agreed to do the same kind of staging right and that staging is what we're calling T and M and T has to do with how big it is right in the one site and how much it's crossed any barriers right this what the barrier question sounds like the most important thing it does although this one here is are they in lymph nodes all right right and the lymph nodes are nearby structures where you know the lymph goes right and so that's one what wrote out and the other one is metastasis right and so yeah the staging has to do with all three I see metastases always happens through the the circulatory system essel Zoar does it also happen to the lymph network and so it's something we're going through the lymph nodes for something like this is that one of the first steps right but getting to the liver and the lung is gotta get into the blood vessel ice ice a lymphatic in your colon connects to a local lymph node right does not connect through lymph only to the IC so it must have gone in I said somewhere I see so that's the the way it looks here and then the final thing here when looking at this cancer is if we go over here this is the greatest depth of invasion you'd ask me about the body's immune function well if you look here now you see how it's kind of loose and there are all these little immune cells that's what these guys are those are witless immune cell we see little round guys those are lymphocytes so that's you she is circle attacked you yeah how do you how can you tell the difference between the lymphocytes and the and the cancer cells because I'm not I thought that's go guys yes no but they're the little round ones so this one right here is a classic cell which is called a plasma cell in which there's a nucleus here and all the rest of this is making antibodies you're not circling that area I'm just drawing so this guy is this one-eyed room right okay you're zooming in on yes giving on that so yeah that's a plasma cell meaning it's a nuclei just want to clarify what you've circled there just cuz it could be a little bit confusing we have this big circle yeah is maybe we should this is why I should leave it to the pros no no no just because I'm getting confused so you're not you're not circling that area then oh it looks like zoomed in right there plasma that's that's a plasma cell that's making antibodies problem right against the term right right and so so that's the immune response in that spot and how do you how do you know that's I mean that looked very similar to the cancer cells Tom this one's a little hard to tell you in real much could you turn up the light and have a very specific look to the network and then these guys over here have little pink granules in them right which is a type of immune cell and then so when looking through here on this death which ones are cancerous here okay so now let me just get over here this one here and then come out just a little bit let me go here is that when looking at these guys these are all inflammation the nearest cancer cell where I could bet the farm are these guys up here oh okay see when you see on this view it becomes more obvious yes they definitely look different they look different so then when you come out here you can see there's the cancer this is the body's reaction to the can see right there I see at the missed zone and there are therapies based on trying to get more of this Wow immune response that's that's that's amazing very cool