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Current time:0:00Total duration:5:56

Video transcript

Voiceover: So let's talk about leukemia treatment. And generally speaking, we treat leukemia with chemotherapy with different types of chemo, chemotherapy. And what chemotherapy is, is chemicals so that's where chemo comes from or chemicals that kill cells. And specifically chemotherapy targets rapidly dividing cells. So cancer cells, leukemia cells are very rapidly dividing cells as we know, and that's how chemotherapy is able to target the leukemia cells. Now something to keep in mind is that, the cancer cells, leukemia cells are not the only rapidly dividing cells inside the body, there are other rapidly dividing cells. And that's something that we'll talk about at greater lengths later on. So the way we administer chemotherapy is actually in three different phases. And the way I like to think of this is kind of like a black ops mission. Something that's very organized and well thought out and very efficient. So the first phase of chemotherapy treatment is called the induction phase. The induction phase. And the induction phase usually last somewhere around four weeks, and the goal of induction, the goal of induction is to kill as many leukemia cells as possible. The goal is to kill all of the leukemia cells. And does this happen in four weeks? Well not necessarily all of the time, but that's our goal. Now, at the end of the four weeks, we don't just assume that we've been successful in killing all of the leukemia cells. We, we double check to see if we've been successful. And the way that we do that is by taking a look inside the bone marrow. So if this is the bone, we'll take a needle, we'll insert it inside the bone, and you guys know where I'm going with this, and we'll draw out some fluid. So we'll do a bone marrow aspiration, and what we hope to see is that all of the cells inside the bone marrow are normal cells, there are no more leukemia cells left, that there are only normal blood cells inside the bone marrow. And if that's the case, if we've killed off all of the leukemia cells, we say that the patient has gone into remission. And something that you should keep in mind is that remission is not the same thing as a cure. So that's because that, if we, if a patient is in remission, the cancer cells are gone, but they can still come back, they can still recur, and that's why remission is not the same thing as a cure. So that's the first phase of chemotherapy treatment. The second phase of chemotherapy treatment is called the consolidation, consolidation phase. And the consolidation phase has two goals, the first goal is to kill off any of the remaining leukemia cells. So if there are any leukemia cells left behind from the induction phase, we aim to kill them off. And the second goal is to prevent the spread of the leukemia into the brain. So to prevent the leukemia cells from traveling to the brain, and the way we do that is by specifically injecting the chemotherapy, injecting the chemotherapy into the CSF, which is the fluid that's surrounds the brain. And the reason why we have to inject it into theirs because when we, the way we normally administer chemotherapy into the blood, it doesn't readily penetrate into the brain. So we have to specifically inject it in into the CSF, and hopes that it will reach the brain in that way. Okay, so that's the consolidation phase. And the last phase of chemotherapy is called the maintenance, maintenance phase. And the maintenance phase usually last between two or three years and in the maintenance phase we usually use the same chemotherapy agents as in the induction phase, but we administer them at a low dose. So administer at a low dose. And the goal over here is to prevent the leukemia from coming back, so prevent it from growing. So chemotherapy is usually the main way, the main method that we use to treat leukemia. If however we know that we have a patient that is at high risk of leukemia traveling to the brain, or if the patient already has leukemia inside the brain, we use radiation, radiation specifically to the brain to kill off those cells. So if, for example if this is a patient over here I'm going to draw a stick figure of a patient. We're going to use some external beam radiation. So that's my external beam, and it's radiating the brain to kill off any leukemia cells in the brain. And something really important with this is that we never give this to kids who are under five years old. And that's because under the age of five the brain is still growing and administering radiation to the brain in a patient that young prevents the brain from growing the way that it should and it can lead to cognitive and psychological impairment. So that's, that's something to be mindful of. Now if we have a patient who has a leukemia that's resistant to chemotherapy or radiation, or if we know that the patient has a leukemia that tends to be very resistant or hard to treat. We can try bone marrow transplantation, we can try bone marrow transplantation as a last ditch effort. So what we do over there is we use the bone marrow from a donor and we can use that to replace the patients bone marrow. And so that in a nutshell is how we treat leukemia.