Transcription
Hey guys, it's Medicos is Perfection Alice. Welcome to my channel and welcome to my playlist on hematology and oncology. In the previous video, I've talked about chronic myeloid leukemia. Today, let's talk about the blast crisis in CML.
As you know, chronic myeloid leukemia is a chronic leukemia, which means the cells are more mature, such as the neutrophil. But in the blast crisis, there is transformation into the blast phase, which is an earlier, more immature stage, such as these blasts. That's why blast phase in CML behaves exactly as an acute leukemia, which is not fun.
On my previous lecture titled "Introduction to Leukemia and Lymphoma," we have discussed this slide. Akif leukemia: you have blasts greater than, usually, 20%; this is acute leukemia. Chronic leukemia: you have mature cells called cytes, and blasts are usually non-existent or less than 10%. CML is a chronic leukemia, which means blasts should be less than 10%. When there is a transformation to the acute leukemia, you have blasts greater than 20%; this is called the blast crisis.
And back to our famous slide: chronic myeloid leukemia is supposed to be here, but now it's going back to the blasts, to the immature cells. This is called blast crisis or transformation.
Now let's turn our attention to the phases of chronic myeloid leukemia. You have three phases: chronic phase, accelerated phase, and blast crisis. In the chronic phase, usually patients are asymptomatic or have mild symptoms. They are very responsive to treatment in this phase, and most patients are diagnosed here. Then, if you do not treat them, or they go to the accelerated phase. Here we have splenomegaly, basophilia, and we start seeing some blasts. Then they transform to the blast crisis; 20% of the cells are blasts. Some sources argue that they are indeed 30%. Anyways, lots of blasts. When you see lots of blasts, this is, by definition, acute leukemia, so clinically it behaves as an acute leukemia. This is refractory to treatment; you have blasts and a high base of failure. And since it's refractory to treatment, this is the cause of death from CML due to rapid cell turnover in this phase. You'll have hypophosphatemia because, as you know, phosphate is more prevalent inside of the cell than outside of the cell, so rapid cell turnover will lead to phosphate exiting the cell because these will rupture.
So, blast phase or blast crisis, clinically speaking, you have a patient with fever, usually unexplained fatigue, as well as infection, significant weight loss, some platelet abnormalities could be bleeding or thrombotic events such as thrombi or strokes. Increased base of failure will lead to increased histamine release, leading to pruritus, which is a fancy word for itching, diarrhea, and flushing. On the lab, you'll find blasts greater than 20%, which is, by definition, an acute leukemia, and you will have basophilia.
Okay, here is a mnemonic for you: blast phase—blasts and basophils—because it's refractory to treatment.
In this order, I've uploaded this video, and this is today's video, so make sure to subscribe so that you never miss a new video. That's it for today, guys. Thank you so much for watching. Please consider subscribing to my YouTube channel. I'd like you to see me on Facebook, where you can communicate, comment, and you have extra stuff there, or you can message me directly. Also, follow me on Soundcloud. If you'd like to support this channel on Patreon, you will receive early access to all of my videos, plus some extra notes and extra stuff. And thank you so much. This is Medicos is Perfection Alice. I'll see you next time. Be safe, stay happy, and study hard.