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- [Voiceover] Alright, so let's talk about Multiple Myeloma. And I'd like to start by introducing you to Babs. And Babs is a 70-year-old lady and over the past few months she's been becoming really crabby. And she has all sorts of complaints. And so, because of this, I'm going to call her "Babs the Crab." So, what are some of the complaints that Babs has been experiencing? Well, first, she's been having some GI symptoms, things like constipation, nausea, and a poor appetite. And I'll just represent that here. She also has been drinking a lot more than normal, and frequently complains of being thirsty. She's also been more tired than normal and some of her family members have noticed that her skin's been maybe just a little bit more pale than it usually is. So, I'm just going to write that in here as "fatigue" and "pallor," and then we can kinda make her skin look a little bit more pale here. And lastly, she's been complaining of this just constant, dull lower back pain. Now, although each one of Babs complaints here are in themselves fairly non-specific and vague, when you take them as a whole, they are actually fairly telling. And an astute medical provider would likely be concerned that she may have Multiple Myeloma. Now before I talk about why these symptoms here are consistent with Multiple Myeloma, let's first just answer the question, "What is Multiple Myeloma?" And Multiple Myeloma is a malignancy or a cancer of plasma cells. And I'm going to just also star this here, because it's very important. Well, what are plasma cells? Well, plasma cells are a type of blood cell that produce antibodies and antibodies are part of the immune system and they help our bodies fight infection. And there are four major mechanisms of Multiple Myeloma that I want to address here. And this first mechanism is a monoclonal production of immunoglobulins or antibodies. And I'm just going to abbreviate immunoglobulins, Ig. Well, what do I mean by this? Well, when you have a malignancy of a plasma cell, that malignancy actually starts in just a single cell and that single cell replicates over, and over, and over. So what you get is this increased production of only the type of antibody that that original cell produces. And, these immunoglobulins are actually proteins, and the proteins, can precipitate and deposit in different areas of the kidney. And this results in renal failure, or kidney failure. The next mechanism is an increased bone turn-over. So these malignant plasma cells release certain factors into the blood that affect the bone, and they cause the bone to turn-over, to break-down in a sense, and this increased bone turn-over results in what are known as lytic bone lesions. And they predispose the bone to fractures. By this I mean they make the bone more likely to break. And the most likely site of these fractures is in the spinal column. And as the bone is being turned over and being broken down, it's also releasing calcium. So this results in hypercalcemia. The next mechanism is crowding of the bone marrow. Now, before I describe this mechanism, I want to briefly go over what bone marrow is. So let me just draw a bone here. So bone marrow is in the center of bones and it's where blood cells are produced. And so, let's just draw in some blood cells here. So maybe some of the cells that produce red blood cells, and some of the cells that produce platelets, and then some of the cells that would produce plasma cells. So this would be a normal bone marrow, producing the different types of blood cells. But, when you have a malignancy of these plasma cells, the one type of plasma cell is just growing uncontrollably and you get this crowding out of the bone marrow by only the plasma cells, so the bone marrow is no longer producing enough red blood cells or platelets. And so, this results in anemia and thrombocytopenia. And anemia refers to a low level of red blood cells in the blood, and thrombocytopenia refers to a low level of platelets in the blood. And the last mechanism is a decreased production of normal immunoglobulins, so once again I'll abbreviate that Ig, which are antibodies. And, if the body isn't able to produce normal antibodies, then the body is not able to adequately fight off infections. So individuals with Multiple Myeloma have an increased risk of infection. So you can see that some of these colors here in the different mechanisms of Multiple Myeloma correlate with the symptoms that Babs the Crab was experiencing, and that isn't a coincidence. And I'm going to start here with the hypercalcemia. And when someone has hypercalcemia, they will oftentimes experience certain GI symptoms such as constipation, nausea, and a poor appetite. You can remember this with this C here, and then I'll highlight the C over here in Crab. And then the next one is this renal failure, and when someone has renal failure, sometimes their kidneys won't be able to retain water so the individual will become very thirsty. And so that's why Babs here had this increased thirst, cause she was having renal failure. And so we'll just highlight the R here in renal failure, and then the R over here in CRAB for renal failure. The next is the anemia, so what anemia means is you have a decreased amount of red blood cells. And red blood cells carry oxygen to the body. So, if you don't have enough red blood cells, your body can't get enough oxygen and so the body becomes fatigued. The skin also becomes pale, so you have this fatigue and pallor due to the anemia. And so for A for anemia we'll just highlight the A in CRAB over here. And then lastly, you have these lytic bone lesions that have an increased risk of fractures. And so frequently people with Multiple Myeloma will have this low back pain. And we'll highlight the B there for bone or back, and that is the B in CRAB. So the reason that Babs the CRAB was all crabby is because CRAB is actually just an acronym to help you remember what is happening in Multiple Myeloma. Someone who has Multiple Myeloma will experience hypercalcemia, renal failure, anemia, and bone lesions that cause back pain. Alright, so how do you diagnose Multiple Myeloma? Well you can really just follow through each of these categories to help get an idea. So with the renal failure, you can check certain blood levels, like BUN and Creatinine which can show signs of renal failure. And then you can also do a test called an Electrophoresis, and what this is is a special test that detects this monoclonal production of IgG and it can be done on either the serum or the urine, and the result it has is known as an M spike. And this is a little bit confusing, and I don't want to get into all the nitty-gritty details of it, but just remember that electrophoresis will detect this monoclonal production of Ig. And then, for the lytic bone lesions, to diagnose that, you can do a bone scan. Hypercalcemia is just detected in the blood. For the anemia and thrombocytopenia, the diagnosis can be through a complete blood count. Which will show a decreased red blood cell count and decreased platelet count, or you can see this crowding of the bone marrow on a bone marrow biopsy. So these are the tests that you would do to diagnose Multiple Myeloma. Now I'm going to just briefly address the treatment of Multple Myeloma. Now, like many areas of cancer treatment, the specific methods for treating Multiple Myeloma rapidly change, so I'm not going to address any specific medications that are used, but just talk about a general approach to treating Multiple Myeloma. And there is two general approaches. The first approach is to treat the symptoms of the disease, and cause disease regression. And this is accomplished through different medicines as well as chemotherapy. And then the other approach for treatment of Multiple Myeloma is curative. And this is achieved through a bone marrow transplant. I'll just abbreviate that BMT. And so obviously when you have a cancer, the goal is to cure the individual; however, bone marrow transplants can be very hard on people, and since Multiple Myeloma like in Babs here is most common in the elderly with a median age right around 70 years old, oftentimes bone marrow transplants aren't able to be performed because the patient just would not handle the treatment very well. And so, the mainstay of treatment are certain medications as well as chemotherapy. So just remember that Multiple Myeloma is a malignancy or a cancer of plasma cells, and that CRAB is an acronym for the effects of Multiple Myeloma, with C representing hypercalcemia, R for renal failure, A for anemia, and B for the lytic bone lesions and low back pain.