Transcription
Hey everyone, welcome back to my channel, Mother Causes Perfection Alice. I'm so excited; finally, it's coming. We're talking about Leukemia and Lymphoma in an introduction. Now, if you go to my Patreon page, I've already published many videos; therefore, my Patreon subscribers, if you are in a hurry, you would like to get access to all of them, just for one dollar a month, you can get access to my leukemia and lymphoma videos just right now, before everybody else. If you don't have money, that's fine; I'm releasing all of these videos for free on YouTube later. So please subscribe and please share my videos. Okay? If you get this introduction today, okay, Leukemia and Lymphoma becomes like a piece of cake for you to understand. It's really easy, but this introduction is crucial to get the basics straight. Okay?
Leukemia and Lymphoma, as I've told you before, leukemia means cancer cells coming from the bone marrow and circulating through the blood circulation. Lymphoma is a solid tissue, so like lymph nodes, spleen, liver, mucosal-associated lymphoid tissue; it's a solid organ. So leukemia is kind of liquid-ish; lymphoma is solid. We understand more. Okay? Is it the lemon or the lemonade? Is it a solid or is it liquid? Is it lymphoma or is it leukemia? That doesn't mean that we cannot convert the lemon into lemonade, and we can get these nice little seeds, plant them and form lymphoma. Okay? So it's not mutually exclusive; it's not an either/or. Lymphomas can have leukemias, and leukemias can have lymphomas, but the basic rule is lymphoma is a solid tissue mass—lymphoma mass in the lymph node or in any other lymphoid tissue. Leukemia—emia means blood; loge means white blood cell—malignant white blood cells in your bloodstream. Where did they come from? From the bone marrow, so they will be in the marrow and in the bloodstream. Leukemia is liquid; lymphoma is solid, roughly speaking. Lymphoma: solid tumor or solid mass in the lymph node or the mucosal-associated lymphoid tissue, spleen, or bone marrow. Leukemia: in the blood. Where does the blood come from? From the bone marrow. Some leukemias also have a lymphoma component; many lymphomas have small components of leukemia. Okay? So they can overlap.
Let's see an example of the overlap: chronic lymphocytic leukemia. From the name, you know it's leukemia, so it's in the bloodstream and, of course, in the bone marrow, but sometimes it goes to the lymph node causing small lymphocytic lymphoma. SLL. When they come together, we call this condition CLL/SLL. Cool. Okay? If you suspect leukemia or lymphoma, always order a peripheral blood smear. In fact, to diagnose leukemia especially, we need two things: we need the peripheral blood smear plus we need bone marrow biopsy. These two are big deals. Another example of the overlap is Burkitt's lymphoma. Burkitt's lymphoma sometimes can have Burkitt's leukemia—same stuff and same chromosomal translocation as we will discuss later. Your major blood disorders other than anemia: we have proliferative disorders, like increasing proliferation or cell division, can be myeloid or lymphoid. As you know, myeloid will be all of these; lymphoid will be some of these hematological malignancies, which are leukemias and lymphomas, and don't forget multiple myeloma. Cool. Marrow failure: aplastic anemia. We have discussed it in a previous video. A special type of aplastic anemia is pure red cell aplasia—thank you, Parvo B19 virus—in people who have a lot of hemolysis, such as sickle cell anemia patients and beta-thalassemia major patients. Also, myelodysplastic syndromes, or MDS. We are going to discuss MDS in a later video, but for now, just remember MDS is an intermediate state between normal and acute myelogenous leukemia. That's why the whole purpose of the treatment is to prevent this patient from progressing to acute myeloid leukemia; we would like to stop them right there. Fine. So marrow failure: the hallmark will be pancytopenia. How about hematological malignancies—malignancy of white blood cells? You will have lots of white blood cells in the blood and the bone marrow. Proliferative disorders: increased blood cells—again, pretty straightforward.
So now, benign leukocyte reaction can be quantitative and qualitative; those are not to worry about because they are benign, such as leukemoid reaction. Okay? Don't confuse leukemoid with leukemia. Leukemoid is benign; leukemia is malignant. Okay? Also, local erythroblastosis. Fine. How about the quantitative? You have neutrophilic leukocytosis, as we have discussed before in my video on white blood cells. White blood cells include what? Neutrophil. Increase neutrophil count is called neutrophilic leukocytosis. Increase eosinophil count is called eosinophilia. Increased lymphocytes: lymphocytosis, such as in infectious mononucleosis, as we will discuss later. Increase basophils is called basophilia. Increase monocytes is called monocytosis. Pretty cool. So here are your blood disorders other than anemia: proliferative disorders, hematological malignancies, marrow failure, and benign leukocyte reactions. Now, pay attention. Did you see CML is here with leukemia and it's also here with proliferative disorders? Multiple myeloma is here with hematological malignancies as well as here with proliferative disorder. So they can overlap. A big difference between aplastic anemia and MDS: okay, both of them have pancytopenia; however, aplastic anemia, the bone marrow is hypocellular—few cells in the marrow—and MDS has hypercellular marrow with dysplastic cells. Why do we hate neoplasia so much? By the way, neoplasia can be either benign tumors or malignant tumors that we call cancer. Neoplasia by itself doesn't necessarily mean cancer. Many students confuse the two. Neoplasia can be benign or malignant. So normal proliferation or normal cell division is polyclonal, which means multiple cells are dividing into many more cells. It's a regular process, and it's reversible. Neoplasia is different; it's monoclonal—one crazy cell, for some crazy reason, decided to proliferate, and this is neoplasia. Cancer is like this. Okay? Just one crazy cell. Okay? It's crazy; it's irregular, and it's irreversible. Okay?
Be more specific on the molecular level. Let's take the B lymphocytes. Here is normal lymphocytosis. Let's say that B lymphocytes are proliferating, maybe to fight an infection. That's cool. You know that B lymphocytes will secrete immunoglobulins. These immunoglobulins have heavy chains and light chains. Light chains can be either kappa or lambda. So let's say that before cell division the ratio between kappa and lambda was 3 to 1. After proliferation, 6 to 2—the ratio is the same; we preserve the ratio. This is normal; we are so happy. Now let's see B-cell lymphoma; let's see cancer. Cancer behaves weirdly, in a crazy way. Okay? We have a single cell, for some crazy reason, has decided to go like this. So the ratio here is 100 to 1. This is not normal; that's why cancers are bad. While hyperplasia can be good. Now I know you will say hyperplasia can be pre-malignant. I know, but let's keep it simple. Cancer is monoclonal; hyperplasia is polyclonal; that's why cancers are evil on the molecular level. Now pathologists can tell you if this cell is normal or malignant under the microscope. They have something called criteria of malignancy, but this is not our topic today. Oh, as you know, hematological malignancies—monoclonal—can be leukemia, lymphoma, and myeloma. Leukemias are four big subtypes: acute lymphoblastic leukemia, acute myelogenous leukemia, chronic lymphocytic leukemia, chronic myelogenous leukemia. Lymphomas can be either Hodgkin's lymphoma and anything else we call it non-Hodgkin's lymphoma. Myeloma, of course, is the multiple myeloma—a malignancy of the plasma cells. Plasma cells are fully differentiated B lymphocytes that can secrete antibodies into the blood. We are studying any topic for the first time. What's the first question? What's the definition of leukemia? Malignancy arising from bone marrow stem cells. Malignancy is by definition monoclonal, as I've told you. These leukemic cells arising from the bone marrow will do three things: first, they will replace most of the bone marrow cells—the normal cells—crowding out the normal hematopoiesis. There is no more normal hematopoiesis; you'll end up with anemia and infections and mucosal bleeding. These evil cells will enter the peripheral blood, and they will metastasize throughout your body. Incidence of leukemia is more common in adults than in kids, more common in males than females. Which one of the leukemias is the most common? ALL is by far the most common leukemia and the most common cancer in children, period. End of issue. Can you guess the type of leukemia by age? Yes, just by knowing the age of the patient and that he or she has leukemia, you can guess, roughly speaking, what type of leukemia does he or she have. So if it's a newborn up to 40 years old, it's usually ALL. 42-60: AML or CML. More than 60: the old guys, CLL.
Leukemia classification: historically, we have been classifying leukemia into acute and chronic. What's the difference? Acute: the patient is young; the cells are immature. So the patient is kind of immature, roughly speaking, and the cells are immature. That's how you can remember it. Yes. And mature cells are called blasts. On the other hand, chronic leukemia: it's chronic; it takes time. The patient is older; the cells are more mature because we have more time. So we call them cytes, not blasts. Of course, as you know, like erythrocytes are mature, but erythroblasts are cytes. Acute: young patient. Chronic: older patients, generally speaking. In this acute leukemia, blasts constitute more than 10% of your bone marrow. Chronic: these blast cells are less than 10% because the majority of the bone marrow is mature cells—cytes. Then, acute leukemia: we have ALL and AML. Again, these have lymphoblasts; that's why we call it acute lymphoblastic leukemia. On the other hand, chronic lymphocytic—not lymphoblastic—leukemia. These CLLs have a lot of lymphocytes in the blood and have something called smudge cells. If you have tried to Photoshop before, you know exactly what I'm talking about. There is something in Photoshop called smudge tool. You get the smudge tool, and you smudge this nice rounded shape, and you will end up with something like this. Okay? This is normal, and this is kind of smudged, like blurry and hazy like this. This is called a smudge cell. Next, we have acute myelogenous leukemia; they have the myeloid blasts, and we have chronic myelogenous leukemia; they have the myelocytes. Cool. The lemon, not the lemonade. Oma means mass, lymph tissue—solid tumors of the immune system in the lymph tissue, right? So lymphoma can be Hodgkin's or non-Hodgkin's, depending on what—on the Reed-Sternberg cells. When we have these cells, we call it Hodgkin's lymphoma. Everything else is non-Hodgkin's lymphoma. Non-Hodgkin's can be B-cell or T-cell. B-cell can be aggressive, so we treat this with aggressive chemotherapy, or can be indolent; we treat this with watch and wait most of the time.
Last time: leukemias—the lemonade—acute or chronic. Acute: cells are immature; patients are young and immature. The immature cells are called blasts. Chronic leukemia: patients are older; their cells are wiser, but they are still looking cells. I'm just kidding. Okay? Acute has ALL and AML. Chronic has CML and CLL. Lymphomas, on the other hand: tumor or malignancy of the lymphoid organs, such as the lymph node. Lymphoma can be Hodgkin's; these include the Reed-Sternberg cells. Non-Hodgkin's; they can be B-cell or T-cell. B-cell can be aggressive or indolent. What a great introduction! Now we are ready to discover each of these leukemias and lymphomas in separate videos, but if you get this video, you get the idea. Oh, even though we haven't discussed any of these leukemias in detail, I'll tell you, you'll be able to answer this question: you have a 67-year-old male. Okay? By the way, I know the answer, right? Then, just by the age of the patient. Okay? But I'm not going to tell you. Let's continue and read the question. Totally asymptomatic. Cool. Physical exam is normal. Cool. One routine CBC—complete blood count—the hemoglobin, hematocrit, and platelets are within normal limits. Nice. White blood cells are 51,000. Lymphocytes are 78% instead of 30% of the total white blood cells. They should be 30; now there are 78. This is called lymphocytosis, but this is—this is not like a normal reaction. 51,000 is a lot; this is leukemia for sure. Okay? And on peripheral smear, we got smudge cells. So what's the correct answer? CLL. Just by the age of the patient, CLL is very likely. Okay? Which stage of CLL? We will discuss CLL later, but this patient only has leukocytosis; there are no lymphadenopathy, no splenomegaly, no anemia, nothing—only lymphocytosis. This is stage zero; has a very good prognosis. Cool. How to manage CLL if he is stage zero? We watch and wait, of course. We follow up; we do routine tests to know if he is progressing to other stages or not, but the management is basically watch and wait. Thank you so much for watching. If you'd like to see previous videos before everyone else, go to my Patreon page. A lot of leukemia videos are already on my Patreon page for my Patreon subscribers. Anyway, please share these videos. Thank you so much for your support. Thank you so much for your comments. I'll see you soon. Until next time, be safe, stay happy, and study hard.