Bone Marrow Transplant Info
If you haven’t been there already (this is the same link as in the Introduction post) and are interested in a good primer on bone marrow transplants (BMTs), there is a book called Bone Marrow Transplants: A Book of Basics For Patients which is written by a lay person and the first chapter called "The Nuts and Bolts of Bone Marrow Transplants" is accessible online.
If you don’t want to wade through that much information, I will briefly explain BMTs as best I can. First a donor must be found. If one cannot donate their own marrow (autologous transplant), and I cannot because my marrow is diseased, then a matched sibling (allogeneic transplant) is the top choice. Finding a match involves doing a matching called HLA typing, which is done by drawing blood from the recipient and potential donors and then trying to match on all 10 antigens that they look for. There is a 25 to 35 percent chance that each sibling can match on all 10 antigens, meaning that since I have 5 siblings, the chances of finding at least one perfect match is around 75 to 90 percent.
There are some 200+ antigens that they don’t match and often don’t even know what they do and this is a big reason why they like sibling donors more than a MUD (matched unrelated donor), i.e. the other antigens are also more likely to match. However, if there isn’t a perfect match among siblings, they sometimes do a transplant with a one antigen mismatch, but may also go to the national bone marrow transplant registry which contains about 5 million potential donors. The donor then goes through more extensive testing.
Harvest from a donor is done in essentially one of the two following ways:
1. In a bone marrow harvest, a large needle is used to extract bone marrow from the top rear of the pelvis in several places and usually under a general anesthesia. There may be a little soreness for a day or two and the total marrow taken is about 2% of the total which the body replaces in four weeks.
2. A peripheral blood stem cell harvest which involves daily injections of a drug called neupogen for 4 days starting on a Thursday, followed by a harvest from the blood on Monday using a procedure not unlike the one I did for platelet donation where blood is drawn from one arm, processed by a machine that extracts the stem cells, and then replacing the blood in the other arm. The neupogen causes the donor’s bone marrow to produce so many white blood cells (20 times as much as normal?), that they and stem cells are forced into the blood stream. The marrow returns to its normal production rate when the drug is gone and the side effects can include achiness and maybe even a slight fever, but only for a day or two. The drug has been around for 15+ years and there seems to be no short or long term risk.
After a donor is found, the transplant recipient is “conditioned” for 6 days with chemotherapy and/or radiation to kill off essentially all of the bone marrow in the case of a full transplant, or much of the marrow in the case of a “mini” transplant. Since there is no marrow to produce all the blood parts, transfusions are required, and the donated marrow or stem cells are also implanted intravenously. The cells circulate and when they get to where the bone marrow belongs, they recognize that that is where they are to implant and do so. It then takes 2 or 3 weeks to see if the transplanted cells start producing blood parts.
Getting someone’s marrow (or stem cells, actually) means I wind up with someone else’s entire immune system. This is why the Graft Vs Host Disease (GVHD) is so common and serious, because the job of the immune system is to reject anything that doesn’t belong to it and in this case, nothing in the host will look like it belongs. To prevent the grafted marrow from rejecting the host, drugs are used to suppress immune system. This results in the patient being very susceptible to infections and diseases of all kinds, and for this reason, the 4 to 6 weeks in the hospital are in isolation in a special “clean” room where all visitors are required to wear masks and maybe gloves and other protective coating. Since the GVHD can be a problem for years, even when the patient goes home, precautions must be taken to try to prevent infection, including a mask and gloves when out in public. They say to expect to miss a year of work, although that can be longer or shorter. Working from home will be a possibility.
Other things we found out along the way:
• Dr. P at HUP would probably use stem cells from bone marrow instead of from circulating blood and so would require a bone marrow harvest instead of a stem cell harvest from the blood. Dr. T at T/FCCC would probably use stem cells from the peripheral blood. While there are some indications that the latter can include a higher incidence of chronic GVHD, Dr. T feels there are advantages that outweigh that risk, and Dr. P says it’s a minor detail and that higher risk of chronic GVHD may not be all bad.
• Dr. T would do a “mini” bone marrow transplant (bone marrow transplant or BMT is a term that seems universally to include stem cell transplants). He says that recent studies have shown it to be just as effective with fewer and less severe side effects because of the reduced level of chemotherapy. A mini BMT means they don’t kill all of the bone marrow, but leave some bad cells to be cleaned up by the transplanted immune system.
• More GVHD may not be all bad because it means the immune system is doing its job in fighting foreign entities. If it weren’t doing that well, it also wouldn’t be as effective in getting rid of the diseased marrow. In fact, I saw some statistics that show that if the donor is an identical twin (syngeneic transplant) where the marrow and stem cells are essentially identical, the incidence of recurrence of the disease can be 3 times higher than with a matched allogeneic transplant.
• There are not a lot of restrictions for visitations in the hospital. They don’t want overnight stays or sick people, but that’s about it.
• Dr. T is concerned about my pilonidal cyst and thinks it should be excised before a BMT, but I don’t think he realized how extensive the surgery is and that the recovery could be 6 weeks or more. I’m not sure I can afford that kind of delay. He will consult with my hematologist and pilonidal surgeon about that.
• Dr. T also thinks that the scaling on my ears is a fungal infection and he wants me to see a dermatologist about getting it treated before the BMT.
• Males receiving female stem cells seem to have more problems than others, but I don’t know if that will affect my sister’s candidacy
• The transplant recipient ends up with the unsuspecting donor’s DNA, at least in the blood and maybe other bodily fluids. This means I could wreak criminal havoc with impunity because the DNA is not mine.
If you don’t want to wade through that much information, I will briefly explain BMTs as best I can. First a donor must be found. If one cannot donate their own marrow (autologous transplant), and I cannot because my marrow is diseased, then a matched sibling (allogeneic transplant) is the top choice. Finding a match involves doing a matching called HLA typing, which is done by drawing blood from the recipient and potential donors and then trying to match on all 10 antigens that they look for. There is a 25 to 35 percent chance that each sibling can match on all 10 antigens, meaning that since I have 5 siblings, the chances of finding at least one perfect match is around 75 to 90 percent.
There are some 200+ antigens that they don’t match and often don’t even know what they do and this is a big reason why they like sibling donors more than a MUD (matched unrelated donor), i.e. the other antigens are also more likely to match. However, if there isn’t a perfect match among siblings, they sometimes do a transplant with a one antigen mismatch, but may also go to the national bone marrow transplant registry which contains about 5 million potential donors. The donor then goes through more extensive testing.
Harvest from a donor is done in essentially one of the two following ways:
1. In a bone marrow harvest, a large needle is used to extract bone marrow from the top rear of the pelvis in several places and usually under a general anesthesia. There may be a little soreness for a day or two and the total marrow taken is about 2% of the total which the body replaces in four weeks.
2. A peripheral blood stem cell harvest which involves daily injections of a drug called neupogen for 4 days starting on a Thursday, followed by a harvest from the blood on Monday using a procedure not unlike the one I did for platelet donation where blood is drawn from one arm, processed by a machine that extracts the stem cells, and then replacing the blood in the other arm. The neupogen causes the donor’s bone marrow to produce so many white blood cells (20 times as much as normal?), that they and stem cells are forced into the blood stream. The marrow returns to its normal production rate when the drug is gone and the side effects can include achiness and maybe even a slight fever, but only for a day or two. The drug has been around for 15+ years and there seems to be no short or long term risk.
After a donor is found, the transplant recipient is “conditioned” for 6 days with chemotherapy and/or radiation to kill off essentially all of the bone marrow in the case of a full transplant, or much of the marrow in the case of a “mini” transplant. Since there is no marrow to produce all the blood parts, transfusions are required, and the donated marrow or stem cells are also implanted intravenously. The cells circulate and when they get to where the bone marrow belongs, they recognize that that is where they are to implant and do so. It then takes 2 or 3 weeks to see if the transplanted cells start producing blood parts.
Getting someone’s marrow (or stem cells, actually) means I wind up with someone else’s entire immune system. This is why the Graft Vs Host Disease (GVHD) is so common and serious, because the job of the immune system is to reject anything that doesn’t belong to it and in this case, nothing in the host will look like it belongs. To prevent the grafted marrow from rejecting the host, drugs are used to suppress immune system. This results in the patient being very susceptible to infections and diseases of all kinds, and for this reason, the 4 to 6 weeks in the hospital are in isolation in a special “clean” room where all visitors are required to wear masks and maybe gloves and other protective coating. Since the GVHD can be a problem for years, even when the patient goes home, precautions must be taken to try to prevent infection, including a mask and gloves when out in public. They say to expect to miss a year of work, although that can be longer or shorter. Working from home will be a possibility.
Other things we found out along the way:
• Dr. P at HUP would probably use stem cells from bone marrow instead of from circulating blood and so would require a bone marrow harvest instead of a stem cell harvest from the blood. Dr. T at T/FCCC would probably use stem cells from the peripheral blood. While there are some indications that the latter can include a higher incidence of chronic GVHD, Dr. T feels there are advantages that outweigh that risk, and Dr. P says it’s a minor detail and that higher risk of chronic GVHD may not be all bad.
• Dr. T would do a “mini” bone marrow transplant (bone marrow transplant or BMT is a term that seems universally to include stem cell transplants). He says that recent studies have shown it to be just as effective with fewer and less severe side effects because of the reduced level of chemotherapy. A mini BMT means they don’t kill all of the bone marrow, but leave some bad cells to be cleaned up by the transplanted immune system.
• More GVHD may not be all bad because it means the immune system is doing its job in fighting foreign entities. If it weren’t doing that well, it also wouldn’t be as effective in getting rid of the diseased marrow. In fact, I saw some statistics that show that if the donor is an identical twin (syngeneic transplant) where the marrow and stem cells are essentially identical, the incidence of recurrence of the disease can be 3 times higher than with a matched allogeneic transplant.
• There are not a lot of restrictions for visitations in the hospital. They don’t want overnight stays or sick people, but that’s about it.
• Dr. T is concerned about my pilonidal cyst and thinks it should be excised before a BMT, but I don’t think he realized how extensive the surgery is and that the recovery could be 6 weeks or more. I’m not sure I can afford that kind of delay. He will consult with my hematologist and pilonidal surgeon about that.
• Dr. T also thinks that the scaling on my ears is a fungal infection and he wants me to see a dermatologist about getting it treated before the BMT.
• Males receiving female stem cells seem to have more problems than others, but I don’t know if that will affect my sister’s candidacy
• The transplant recipient ends up with the unsuspecting donor’s DNA, at least in the blood and maybe other bodily fluids. This means I could wreak criminal havoc with impunity because the DNA is not mine.
5 Comments:
Justin sez:
> The transplant recipient ends up with the unsuspecting donor’s DNA, at
> least in the blood and maybe other bodily fluids. This means I could
> wreak criminal havoc with impunity because the DNA is not mine.Sister Lisa was the one who originally asked this question. I note that she's the only female, and is therefore less likely than the rest of us to wind up being the donor. Furthermore, she is also less likely than the rest of us to be implicated in any future crimes actually committed by Justin.
I'm still willing to donate, Justin, and I want you know I'm allowing the HLA typing of my blood to continue in spite of the possibilities of the havoc you might be able to wreak against me. But only because I love you!
Brother Hugh
The DNA will now be yours TOO. You'll still have to have some way to deflect suspicion to the sibling from whom you get the transplant; a better alibi or apparently less motive. I'm also still willing to donate since you'll have a hard time implicating me because I live so far away.
Brother Bruce
In a peripheral blood stem cell harvest, does the injection of Neupogen always run from Thursday to Sunday? Why? Is there some relationship to the work week? If so, what about people whose days off are not Saturday and Sunday or who work more or less than five days a week?
I'm not sure whether the injections are always started on Thursday, but I believe it is done that way so the harvest can start on Monday. I also believe that the injections can be done by anyone qualified to do so and does not require trips to a hospital or doctor.
From Lisa:
It was actually brother Wayne who first suggested the criminal angle.
I suspect the Thurs-Mon timing is because of the schedule of the physicians and other staff.
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