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Leukemia classifications
Learn how leukemia can be classified as an acute or chronic and myeloid or lymphoid disease. Created by Nauroz Syed.
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- Does the T in T-lymphocyte and the B in B-lymphocyte stand for something?(11 votes)
- Actually the T- in T-lymphocyte means that it matures in the thymus which is primary lymphoid organ, and the B- in B-lymphocyte stands for bore marrow which is the site for B-lymphocyte development and maturation. Bone marrow is also a primary lymphoid organ.
I hope that's helpful. :)(21 votes)
- which one is worse? Chronic or acute?(5 votes)
- It is always hard to say which cancer is worse. Currently, we have associated certain mutations in the hematopoietic stem cells as associated with a better or worse prognosis, but in reality many factors are involved in the care of a patient with leukemia. It also depends on when the CA is caught. Acute leukemia caught early in a younger man has a high chance of being "cured." Currently, our cure rate for ALL in children is >90%. Our cure rate for CLL is pretty poor. But, in CML, with the philadelphia chromosome mutation, our cure rate is high, because we now have targeted drug therapy. It all depends! CA is not something that we can never have 100% certainty. (As is most medicine... But that's a talk in itself...)(5 votes)
- 5:40If I wanted to leave it as broad as "just in the myloid group" would i say Acute/Chronic Myeloid*ic* Leukemia? Or could I just say Acute leukemia or even just Myeloidic Leukemia?(3 votes)
- Sooo. there was answer down there that said atomic bombs can actually cause lekimeaia is that true, and if so how come people across the world have it? Was it spread, or can it happen naturally like i think?(3 votes)
- Atomic bombs give out radiation. Radiation causes cancer. But atomic bombs aren't the only source of radiation, there are other sources of radiation too... like nuclear power stations or even X-Rays. Also, carcinogens (such as asbestos) can cause cancer.(2 votes)
- At7:23, what is the thymus?(2 votes)
- A lymphoid gland high in the chest, between the lungs. It shrinks away after puberty .(2 votes)
- What is the prognosis for AML/CML/ALL/CLL and the ages for prognosis. I know CML has new drug therapy that has raised the 5 year survival rate to 96% but I am more curious about the other three. I know ALL is more common in pediatric patients and CML is more common in adults but I haven't been able to find specific prognosis like I did for CML.(2 votes)
- Does Leukemia affects more children or adults or it's about the same? What cause the Hematopoietic stem cell to create a bad cell or leukemic cell ?(2 votes)
- I'm not sure about your first question, but to answer your second question, the hematopoietic stem cell sometimes creates a cell with a gene mutation, which can happen because of exposure to radiation or chromosome translocation. This creates a leukemic cell.(1 vote)
- so does leukemia have a cure?(2 votes)
- At3:30, what is the average life span of a normal cell?(1 vote)
- It is different for different cells. Skin cells, epithelium, 7 days. Red blood cells, 120 days. Neurons, 90 years +, hopefully your entire life.(2 votes)
- why can't it be a fully grown cell have leukemia ? to have leukemia and then it start having the to got it's DNA corrupted won't it will still be helpful to the body and it would stomp out virus faster and help you so why can't a fully grown cell have leukemia?(1 vote)
- Most of the differentiated leukocytes have short lifespans and don't normally divide any further. A neutrophil, for example, lives for less than 4 days after leaving the bone marrow. That's not enough time for a mature cell to collect mutations that let it divide uncontrollably, so they don't cause leukaemia. The progenitor cells, on the other hand, have much longer lifespans and their job is to make lots and lots of new cells, so it's easier for them to pick up a bad mutation that causes a leukaemia.(2 votes)
Video transcript
Voiceover: 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
megakaryoblastic leukemia. 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 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 the 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, a 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 out 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 so, I want to go back to the diagram that we used to show how leukemias occur. So, we 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 acute leukemia. So, let's compare that with what chronic leukemias look like. So, a 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, this is a picture of chronic leukemia. 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'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 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 versus chronic, where acute 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. And 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 what they're able to do, okay? So, now let's talk about the second way you can split up the leukemias. And 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 drew
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'd 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 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, acute megakaryoblastic leukemia. What cell does that leukemia develop from? Well, if we're talking about
acute, it must come from this row over here, right? And we said acute megakaryoblastic, so that must be this cell right
here, this cell right here. So, an acute megakaryoblastic 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.