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Missy's StoryHer Battle With Hodgkin's Lymphoma
"Courage is about doing what you're afraid to do. There can be no courage unless you're scared." -Eddie Rickenbacker |
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An Autologous Bone Marrow Transplant (BMT) or Stem Cell Transplant (SCT) is a way of using someone's own bone marrow or stem cells for transplantation instead of someone else's. For autologous (pronounced au-tol'-o-gous) transplantation, the patient receives his or her own bone marrow or stem cells that were collected and frozen before receiving very high-dose chemotherapy or radiation. The process usually takes about 3 months. Recovery takes many more months. There is no donor needed for the procedure because in an autologous transplant the patient is both the donor and the recipient of the bone marrow. Patients undergoing autologous transplantation are at lower risk of infection than are those receiving allogeneic (donor) transplants. An autologous transplant is possible if the disease afflicting the bone marrow is in remission or if the condition being treated does not involve the bone marrow. The bone marrow is extracted from the patient prior to transplant and may be "purged" to remove lingering malignant cells (if the disease has afflicted the bone marrow). The main purpose of a stem cell or bone marrow transplant in cancer treatment is to make it possible for patients to receive very high doses of chemotherapy and, in some cases, high doses of radiation therapy as well. They allow patients to be given anticancer drugs or radiation therapy in doses high enough to eliminate the disease and cure the patient. Bone-marrow transplants and peripheral-blood stem-cell transplants both provide stem-cell support, restoring the stem cells depleted by intensive chemotherapy or radiation. Transplant procedures allow patients to overcome the dangerous side effects of the treatment, the destruction of white and red blood cells and platelets. By returning healthy bone marrow or stem cells to the patient after high dose treament, the transplant rescues the patient's body. No immune suppression is required after an autologous transplant. Research has shown that self-transplants of peripheral-blood stem cells help patients recover more rapidly from high-dose chemotherapy and actually restores white cells, red cells, and platelets faster than self-transplants of bone marrow. High-dose chemotherapy with bone-marrow or peripheral-blood transplants has improved cure rates for both leukemia and lymphoma. There are generally four steps in autologous transplants: 1. Induction chemotherapy to
reduce cancer cells in the body as much as possible.
Induction Treatment The first step in the process of preparing for transplant is the induction treatment. The induction chemo is done to establish whether the patient's cancer is responsive to treatment or not before the stem cell harvesting is done. Once the patient has shown response and is stable, the stem cells may be harvested. Induction therapy may also reduce the amount of cancer cells contaminating the stem cell collection that will be re-infused into the patient and provide optimal chances that the high-dose therapy will eliminate most of the remaining cancer cells. Patients who do not respond to induction therapy are referred to as having primary refractory disease and are often not offered the option of high-dose therapy and a stem cell transplant, as it is commonly thought that these patients will not respond to the higher doses of therapy. Collection of the Stem Cells Stem cells are the immature cells in blood that go on to form white and red blood cells, as well as platelets. White blood cells fight infection. Red blood cells carry oxygen. Platelets are the clotting agents in blood. Autologous stem cells can be harvested from the patient's own bone marrow or blood stream prior to the high dose therapy. Transplantation of the peripheral stem cells from the blood stream is sometimes used in addition to, or instead of, traditional bone marrow transplantation. The most common reason for harvesting both blood stem cells and bone marrow is the collection of a low number of blood stem cells during pheresis. When bone marrow is needed about 1% - 5% of the patient's bone marrow is collected and frozen. Pheripheral blood stem cells are harvested in a process called pheresis. Pheresis provides a way to rapidly pump blood from a vein into a machine and then back into the blood stream. Progenitor cells can be collected from the blood stream using a medical device known as a blood cell separator. This is a machine that uses a centrifuge to separate the components of the blood. In this procedure, blood is removed from the patient through an intravenous catheter implanted into the chest or through a large vein in the arm and is run through the machine that collects the progenitor cells and returns the rest of the blood to the patient. The white blood cells and stem cells are collected in a bag. The same machine is used to obtain platelets or plasma at blood centers. Patients are given G-CSF, granulocyte colony stimulating factor (Nuepogen), shots for a series of days prior to pheresis in order to stimulate the number of stem cells in the blood stream. G-CSF causes some of the marrow stem cells to leave the bone marrow and temporarily circulate in the blood. Usually, a pheresis session takes from 2 to 6 hours and can be repeated if enough stem cells are not collected. To obtain enough stem cells, often 2 to 5 pheresis sessions are needed. The collection of stem cells from the bone marrow is a surgical procedure in a hospital operating room, usually under general anesthesia. It involves little risk and minimal discomfort. While the patient is under anesthesia, a needle is inserted into the cavity of the rear hip bone called the iliac crest, where a large quantity of bone marrow is located. The bone marrow is a thick, red liquid which is extracted with a needle and syringe. There are no surgical incisions or stitches involved. The needle that collects the marrow is inserted by puncturing the skin. Several skin punctures on each hip and multiple bone punctures are usually required to extract the bone marrow. In the bone marrow, there is approximately 1 stem cell in every 100,000 blood cells. The bone marrow in the breast bone, skull, hips, ribs, and spine contains the stem cells. In the blood stream, the number of stem cells is about 1/100 of that in the bone marrow. Once collected, the stem cells are then frozen and stored for later transplantation. Each daily collection via pheresis is checked for its stem cell content (CD34+ cells), and once the threshold goal is reached, the collection process will be stopped. Once enough stem cells are collected, the patient does not need to undergo further pheresis. High Dose Chemo After the harvesting of the stem cells, the patient must then undergo very high dose treatments to kill any disease that might be left in the body. This chemo is so strong that it also destroys the bone marrow, which is why the transplant is needed. High dose chemotherapy (HDC, sometimes called the "conditioning regimen" is a lethal dose of chemotherapy, enough chemo to kill off virtually all existing blood cells and the blood cell producing cells in the marrow. Needless to say, this would normally cure the disease, but kill the patient. This is why the transplant is needed. Some additional side effects
of the treatment include:
Transplant The days before the transplant are counted as minus or negative days. The day of transplant is considered day zero. Engraftment of the transplanted stem cells and recovery following the transplant are counted as plus days. For example, a patient may enter the hospital on day -5 for the preparative regimen. The day of the actual transplant is numbered zero. The days following the transplant are counted as positive days. Days +1, +2, +3 and so on, will follow the transplant day. There are specific events, complications, and risks that are associated with each day before, during, and after the transplant. The days are numbered to help the patient and family understand where things stand in terms of treament, complications, and risks and to enable the family to plan for the patient being discharged from the hospital. After the high dose treatment, the patient is no longer able to produce blood cells. Destroying the marrow may be a part of treatment for a disease that has affected the bone marrow or it may be a side effect of treatment. In either case the patient needs a “jump start” to get their bone marrow back to producing blood cells, so the stem cells are put back into the body by way of a catheter or port implanted in the patient's body, which places the cells into the blood stream, rather like a blood transfusion. The stem cells migrate to the bones from the blood stream to stimulate production of new bone marrow that migrates to the cavities of the large bones, engrafts and begins its job of producing normal blood cells, new WBC's (white blood cells), RBC's (red blood cells), and platelets. Two days after the last chemotherapy, the collected stem cells are re-infused. After collection, the stem cells were stored in bags in liquid nitrogen to keep them viable. For the transplant they are thawed at the bedside in a water bath, until they are liquid again. Then the stem cells will be slowly injected with a syringe into the patient's central line. The process lasts 30 - 60 minutes. It may be done in one session or if a number of cells were collected, in a morning and afternoon session on the same day. Possible side-effects include allergic reactions to DMSO, a chemical added to the stem cells to prevent damage during freezing. The possible allergic reactions are quite benign, and can often be prevented or treated with drugs such as Benadryl®. All patients will smell the "garlic-like" smell of DMSO for a while. Blood cell production from the transplanted stem cells usually occurs within about 2 to 4 weeks following the transplantation procedure. With a peripheral stem cell transplant, this usually occurs a lot faster. After the re-infusion of stem cells, the wait is on for the growth of new blood cells. It takes about 7-10 days before the first white cells re-appear. In the meantime, the "old" blood cells will start dying off, and patient is prone to infections and bleeding and most likely will need transfusions of platelets and red cells. Once the white cells and platelets re-appear, they generally return rapidly to the normal range. Transfusions are usually only needed in the first 2-3 weeks after transplant. Getting a transplant is far from easy, but powerful antibiotics, white and red blood cell stimulating factors, and new methods of controlling distressing symptoms after very high dose chemotherapy have made it more tolerable. Complete recovery of immune function takes up to several months for autologous SCT patients. Miscellaneous Information Not all patients diagnosed with Hodgkin's disease or any of the other diseases for which bone marrow transplants are being used are candidates for an autologous SCT. The type of disease, the stage of the disease, the responsiveness of the disease to prior treatment, along with the patient's age and general physical condition are all factors that determine whether a patient is a suitable candidate for an autologous SCT. The most common indications for autologous stem cell transplants are:
There is no living
thing that is not afraid when it faces danger.
Door to the Bone Marrow Transplant Unit,
8th Floor West
Hodgkin's Disease Thank You Page Email: cparker2@sc.rr.com
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