Everyone at Alison has done a great job. Sal and his videos are priceless.
In colon dysplasia, what does STP stand for? Neoplasia is the "Get out of my way" type. Autonomist is a ' mean streak'.?.
This course is great. I still want to know more. Neoplasia>, Carcenoma>. Would like to see more on Dysplasia?
Hyperplasia-> dysplasia-> polyp-> neoplasia-> carcinoma in situ-> cancer Dyspalsia keeps growing as it is autonomous, even if the irritant is removed.
What is colon dysplasia?
Discussion on Dysplasia. Eplains how Dysplasia is different to Hyperplasia. Dysplasia is when the structure is no longer correct. The structure forms a kind of pollup which looks like the shape of a colourless cauliflower. Also shows one of the ways to identify wether the tissue has become cancerous or not (Sarcoma insintu) . Discusses Neoplasia as well which is a new growth which grows on its own.
dyplasis is a growth that isn't doing its job properly not producing enough mucus . dyplasia is here to stay it keeps on growing
This is Sal, and I am still at Stanford Medical School with Dr. Connely.
C: "Sal, we're going to continue. Sal, you're going to have to get one unit of credit for today."
S: "Oh, my mother would be proud!"
C: "So, what we're looking at today is a colon polyp."
S: "So, what we saw in the last video was not a polyp, but an irritated part of the bowel?"
C: Yeah, it was very low lying, it was really just a patch of irritant.
C: We have a bigger piece now, so you can see the glands look tiny here.
S: So on the last slide, about how big would it be on here?
C: It would be about a piece like that. To be fair, it was probably what was underlying this area here.
C: And then, it grew on to be something more.
S: It wasn't this exact one, but it could've grown on to be something like this.
C: Yes. When we have a colon resection, if there's a cancer, there's often a polyp...
...an area, a patch like we saw with hyperplasia.
S: [The patch is] not necessarily where the cancer is, just [the cancer would be close]?
C: Yeah, we find that if people have a colon cancer, they have a lot of pre-cancer regions.
S: So, you can see that their bowel has been going through a lot of trauma.
C: Some of its familial susceptibility, but a lot of it is that they are showing a propensity to do this...
...don't know if it's from environmental exposures or what.
S: I see. So just to remind myself on what we're doing here, you cut out a piece of colon...
...because there was cancer there, and there might be a polyp in the same section
that you cut out, and that 2nd slide where we saw the irritation might be right there.
C: As a matter of fact, it's important you normally wouldn't see this slide in a patient,
because almost all polyps, the colonoscopist is coming in, and they remove it through the colonoscope.
S: Because they don't know if it's cancer or not.
C: They'll remove it, but you wouldn't see the full wall. So right here, that's all the way through t
wall and what you got here is muscle. So this really a full piece of the wall.
C: So this is a larger piece, to show the polyp in its natural environment.
C: So we're going to look at the polyp. First, way out here, the normal architecture
C: So we said there are supposed to be tubes. Luckily, this one is cut right down the middle of the tubes
C: so you can see how big the holes are.
C: So, this is normal architecture there. If I go out a little bittle, you'll see an area here
in which there is a bit of irritation. So, it's a thrown up [?] a bit like we saw before,
but the real trouble is this thing sticking out. And we wonder, what is this thing sticking out.
C: And so, for the medical students, we tell them to think like the pathologists,
First need to look at the overall architecture: This is an abnormal architecture.
We don't usually see a polyp sticking out.
S: In 3D, would it look like a mushroom?
C: Yeah. Actually, they tend to have a folding in the tops so they are more like cauliflower.
C: They don't have much color to them. The colonoscopist, when they look at them,
can kinda tell if there's a chance of cancer because they begin having weird blood vessels.
S: Just to be clear, they're not this purplish color.
C: No, we have to stain these thin-sections or it would be colorless.
C: So now, I am going to draw an area where I'm going to do a comparison. See this box here?
C: So these are cells which are relatively normal. And these [on the top] are cells which are abnormal.
C: A pathologist immediately say, "These look angry."
S: They do! They do look angry! I would say that, too!
C: What's angry about them: First of all, they are not committed to behaving.
C: Proper behavior over here: nuclei belong at the bottom; things you're supposed to do for your job
are at the top. So, when you look at these guys, you're like, "Where's your job?"
C: And so, a few of them are making mucin, but these ones have nuclei of different sizes and shapes.
C: They're just doing their own thing, not producing mucin, all they're doing is growing.
C: Usually there's a playoff between, if you're committed to your specific job, we call it differentiation.
C: So if you're committed to your differentiation, you tend not to have as much propensity to grow,
and if you grow a lot, you tend not to do the differentiation.
C: And so, this is largely that you have this chaos of nuclei, less commitment to the normal structures,
and you're not producing as much.
C: And so, what this is, is this is now called 'dysplasia.' ['Dys' is from Greek for 'mal'; malformation.]
C: We're saying: We don't like their looks. These individual cells look dysplastic in their growth.
C: So then, to tell whether it's cancer: Cancer means, in this organ, that you've grown across this line
in the sand.
S: So, literally, if you've crossed this boundary--cancer.
S: So, even if I'm in the polyp up here and I'm growing uncontrollably,
and mutated and not killing itself [when it should; not responding to apoptotic signals]
you still would not officially call it cancer?
C: No, what happens is that there is a middle-term for a cancer that remains in its usual place:
That's "carcinoma in situ."
C: So, carcinoma in situ means that it's not an invasive cancer,
so most people would not even call it a cancer.
But it's just so wild looking up here, you know that it would [become "real cancer"]
if given chance and time.
S: What we're saying is that if there were carcinoma in situ out here, that it eventually would make
C: Right, it would continue to grow, because there is so little differentiation that you know it would
continue to grow until [it became cancer.]
C: With here, though, it's still dysplasia, where it's upsetting that it's growing so fast,
but what's important about this, is that in hyperplasia, if you took away the stimulus or irritant,
it would go back to normal--this would not [go back to normal.]
S: If the irritant were removed in hyperplasia, it would go away in time.
S: This dysplasia is here to stay.
C: So the key word is "autonomous." So it will grow no matter what.
It doesn't care about clues from neighboring cells, it doesn't need something driving it,
so what you have then is if this is growing, and if it's growing all by itself, it's called a "neoplasia."
S: So neoplasia means showing dysplasia?
C: Dysplasia is when you look at these features, these cells aren't growing right.
C: And then, overall, this lump is a "new growth," a neoplasia.
We reserve the term in the medical field for meaning: It's growing on its own.
S: How do we know it's new? How do we know it wasn't around for a year?
C: I think it was. It probably came from this area here,
and the thinking is that you probably had irritant here, hence hyperplasia,
it would continue to grow--cells divide, cells divide too much,
and then, [mutations occur (cancerous cells are rarely a result of only 1 mistake)],
the cell says, "You know what? From now on, I'm not listening to any clues."
S: And then, its descendants would be crazy, too?
C: Right, they would have a real mean streak. And then they would grow from here.
S: (I see that pattern in my own family!)
C: So here, these are more normal glands, but even these--that's dysplasia.
C: So these are growing without a good pattern of growth.
And overall, this lump, is a neoplasia.
S: So when we say "new," we mean, "newer than the other tissue"?
C: We don't mean newer than the other so much as it's its own thing.
C: New kid on the block.
C: So this one right here is a polyp, it has features of dysplasia, but we see no cancer.
S: How would you know? Oh, because it didn't cross the boundary line.
C: There is a reason why the boundary is important, because if you look here,
these are all the surface cells, down here, these are the vessels that go to the rest of the body.
C: So these are blood vessels, these are called lymphatics,
and what lymphatics are, they take the clear fluid [v. blood fluid]
S: These right here, these are the lymphatics, the clear fluid.
S: Fluid can go back and forth between the blood vessels and the lymph system?
C: Yeah, usually what happens is: Blood comes in an artery like this,
goes on down to these little vessels, and then a little bit of the clear parts of it,
will kind of leak out.
S: The blood cells are too big [to leak]?
C: Yeah. So, some clear stuff comes out, and this is how it returns to the rest of your body,
through these lymphatics.
C: So you can see, you do not want neoplastic cells in here.
S: Right, because once they are in there they can go to any part of the body.
C: Go to a new place, and guess what? Set up shop, new kids on the block, they just do what they wanna.
S: So that's called...I can't pronounce it...
C: Metastasis. So, metastasis would be, if it gets into these things,
it can get out of the colon and go anywhere.
C: So this is one where it is not cancer, it has not invaded these areas where it can [metastasize.]
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