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

Video transcript

so let's talk about leukemia treatment and generally speaking we treat leukemia with chemo therapy with different types of chemo chemotherapy and what chemotherapy is is chemicals so that's where chemo come 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 cell 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 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 in 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 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 often 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 surrounds the brain and the reason why we have to inject it into there is 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 into the CSF in 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 lasts between two to three years and 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 to 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 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 if this is a patient over here I'm going to draw a stick figure of a patient we're going to use in 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 and in a patient that young prevents the brain from growing the way that it should and it can lead to cognitive and psychological impairments 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 we do over there is we use the bone marrow from a donor and we can use that to replace the patient bone marrow and so that in a nutshell is how we treat leukemia