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Current time:0:00Total duration:6:22

Video transcript

you'll very rarely hear anyone say that the patient has leukemia instead they're more likely to say something like the patient has acute mega karaoke clukey mia so what do all of those other words mean well to understand that we'd have to go back to this diagram which at this point is probably showing up in your dreams because of how many times I've used it but we're going to use it this time to show how the different leukemias are divided how they're split up and organized so the first thing I'm going to do is I'm going to divide this diagram in half I'm going to divide it in half horizontally so I'm going to draw this line down the middle and that would split up the cells according to how mature they are right so you'd end up with a row of cells on top that has the most immature blood cells that you could possibly have and a row of cells at the bottom which has some still immature cells but these cells are a little bit more a little bit more developed a little bit further along so this is actually the first way that you can split up the leukemias if a leukemia comes from one of these cells up here it's called an acute leukemia and if it comes from one of these cells down here it's called a chronic leukemia so the first way to split up leukemias is by how immature the originating cell is so what do the words acute and chronic have to do with maturity that seems like a really random word choice right well it's actually not because acute leukemias turns out they grow very fast they grow very fast so a person with an acute leukemia can start to feel sick can start to show signs and symptoms within weeks not years but weeks of the Leukemia forming so it's a very acute onset of disease okay now chronic leukemias turns out they grow very slowly so patient with a chronic leukemia can sometimes go years without having any symptoms at all so it's a very chronic onset of disease so I just want to clarify guys that the whole process by which the leukemia occurs is still the same so we still have this immature blood cell that loses the ability to mature and then starts dividing rapidly and of control that's still going on but what we're doing now is we're fine-tuning what we mean by the word immature so we're asking the question just how immature is that blood cell and and so I want to go back to the diagram that we used to show how leukemias occur so he said that this is what normal blood cell maturation looks like right and this is what happens when leukemia occurs so you have this blood cell that's stuck it's arrested in the immature state and it can't move any further and then it starts to divide really rapidly and out of control so look at the leukemia cells since they're in the first stage of development they're the most immature blood cells that you could possibly have this must be a picture of of acute leukemia so let's compare that with what chronic leukemias look like so chronic leukemia picture looks more like this where you still have these blood cells these immature blood cells that are arrested in their maturation they can't move forward and they start dividing really rapidly the only difference is is that this time the leukemia cells are a little bit more developed they're at the next stage of maturation and not only do these chronic leukemia cells divide really rapidly but they also live longer than the average normal blood cell does so there's a degree of immortality that these chronic leukemia cells have so so this is a picture of chronic of chronic leukemia okay now something else that I think this diagram does a pretty decent job of illustrating is that when you have an acute leukemia your leukemia cells look nothing like your mature specialized cells I mean they bear no resemblance whatsoever and we said before that these cells perform almost no function they just they're just kind of like a waste of space versus if you look at your chronic leukemia cells they don't look exactly like your mature specialized cells but they certainly resemble them just a little bit more right and in terms of their function they leave they leave a lot to be wanted but it's not unreasonable to say that they can do a couple of things correctly you know they won't do everything but they can do a couple of things correctly so this is the first way you can split up the leukemias acute for is chronic we're cute leukemias come from the most immature cells chronic a little bit more developed a little bit more mature cells acute leukemias grow very rapidly chronic leukemias grow slowly an acute leukemia cells bear no resemblance in appearance or in function to the mature specialized cells versus chronic leukemia cells resemble the mature specialized cells a little bit more in terms of appearance and and what they're able to do okay so now let's talk about the second way you can split up the leukemias so this time we're going to take this diagram and we're going to split it in half vertically and if we did that we draw a line down the middle we'd be splitting up the cells not according to how mature they are but according to what cell type what type of cell they are so you would end up with the myeloid cells over here and the lymphoid cells over here and you can leave things as broad as myeloid versus lymphoid or you can specify a little bit more about what cell cell lineage particular cell lineage you're talking about so this is the second way that the leukemias are split up according to cell type so I want to go back to that first example that I gave you in the beginning of the video a cute mega karaoke Mia what cell does that look a me a develop from well if we're talking about acute it must come from this row over here right we said acute mega care you last ik so that must be this cell right here this cell right here so in a cute mega carrier blastic leukemia comes from this cell right here so let's take another example what about chronic lymphocytic leukemia so chronic means that it must come from one of these cells down here lymphocytic must be pointing to either this cell or this cell right one of the lymphocytes and you can leave it as broad as that or you can specify whether you're talking about a B lymphocyte or a t lymphocyte okay so that's how all the leukemias are split up now we're ready to go into the details about the different leukemias