Many patients come to Childrens transplant1 program because of its excellent reputation in the field of pediatric Blood and Marrow Transplantation (BMT). Childrens patients have access to cutting-edge treatments through several clinical trials for blood and marrow transplantation. In addition, the Patient and Family Support Program provides comprehensive mental and psychosocial services and helpful resources for all patients treated in Children’s Center for Cancer and Blood Disorders, as well as patients’ parents and siblings. Although Childrens oncologists refer many autologous transplant patients, Children’s transplant program also works with oncologists at other hospitals in the region and across the country to provide the transplant-related portion of a patient's treatment. Once that part of the treatment is complete, patients return to the care of their oncologist for either further treatment or follow-up. The transplant doctors at Children’s remain available to treat, or help the oncologist treat, any transplant-related complications.
What is an autologous blood and marrow transplantation?
Autologous transplants are the most common of the BMT treatments. Autologous BMT at Children’s is performed for patients with cancer. In this type of transplant, the patient is both donor2 and recipient of blood-forming stem cells, which are collected and frozen until needed following treatment.
What conditions are treated with autologous blood and marrow transplantations?
This therapy is commonly used to treat brain tumors which are difficult to cure with standard chemotherapy3 or radiation and in high-risk neuroblastoma4 , a type of childhood cancer that usually starts in the abdomen or the chest. Autologous transplants are sometimes used in selected patients with other types of hard-to-treat cancer.
Diseases treated by autologous BMTs are generally not disorders that start in or involve the bone marrow5 . Instead, they are malignant (cancerous) tumors located elsewhere in the body that are responsive to high-dose chemotherapy and/or radiation treatment.
The high doses of chemotherapy and/or radiation used to treat those cancers also destroy the patient's bone marrow. Without bone marrow, the body is unable to manufacture blood cells needed to defend against infection, carry oxygen, and stop bleeding.
An autologous BMT enables Children’s transplant doctors to "rescue" the patient from the effects of high-dose chemotherapy and/or radiation treatment by replacing the destroyed bone marrow.Future directions for the autologous transplant program at Children's includes treatment of patients with severe autoimmune and rheumatologic disorders, such as systemic lupus erythematosus, juvenile rheumatoid arthritis, and dermatomyositis.
Preparing for transplantation
- Medical history and physical evaluation: Up to 21 days before beginning the transplantation, the patient will come to the hospital to undergo a complete medical history and physician examination, including multiple tests to evaluate the child's blood and organ functions.
- Stem cell collection:The Blood Donor Center team collects blood-forming stem cells from the patient's blood in a procedure called stem-cell apheresis. This takes place when a patient's blood counts are recovering after a cycle of chemotherapy and often involves placing a temporary central venous catheter in the femoral vein, which is located in the upper part of the leg.
- The catheter is connected to a machine that takes some blood out of the body, separates the white blood cells6 (or leukocytes, which contain the blood-forming stem cells) and returns the rest of the blood to the patient. Patients are typically connected to the machine for three to six hours in order to collect the needed number of stem cells. These cells are processed and frozen for later use by Children’s Stem Cell Laboratory
- Chemotherapy: Two to 10 days before transplantation, patients receive high-dose chemotherapy to treat the underlying disease, but which will often destroy the patient’s bone marrow.
Transplanting stem cells
After chemotherapy, patients receive some of the thawed blood-forming stem cells that were previously removed and frozen. The stem cells are given intravenously, just like a regular blood transfusion.
It takes one to two weeks for the stem cells to mature and begin to produce significant numbers of new blood cells, which is called engraftment7 . Although engraftment begins one to two weeks after transplantation, it can take months or years for the entire immune system to fully recover. The first 100 days is a critical time in the transplant process. Children’s transplant team monitors patients closely for infections and low blood counts, which may require patients to remain in the Washington, DC area for frequent follow-up visits. Depending on a child’s condition, he or she may need to stay in the hospital.
After a patient receives a transplant and passes the infection-risk period, he or she returns home to the care of his or her oncologist for further treatment or follow-up visits. Children’s transplant doctors remain available to treat, or help a child’s oncologist treat any transplant-related complications
Complications or risks of transplantation
- Infections: Chemotherapy suppresses white blood cells, which normally fight and prevent infections. This puts the patient at risk of infections. Infections can be caused by bacteria, fungi, or viruses8 . Antibiotics, antifungal and antiviral drugs are given to prevent and treat infections. Infections that do not respond to the treatment may lead to death in approximately one in 30 patients.
- Veno-occlusive disease (VOD)9 . Blood vessels that lead into and pass through the liver are prone to damage after transplantation. This may result from chemotherapy and may lead to swelling and severe liver damage. The chances of severe VOD are less than 5 percent.
- Nutrition problems. The stomach and intestines are sensitive to chemotherapy. Nausea, vomiting, mouth sores, diarrhea and loss of appetite may occur. Nutrition may be given intravenously or via nasogastric tube feedings until patients are able to eat.
- Low blood counts. While waiting for new stem cells to make normal red blood cells and other blood cells, a patient usually needs transfusions of platelets10 and red blood cells11 , depending on the patient's clinical condition.
- Social and emotional concerns. Transplantation is a challenge to both patient and family. They will encounter disruption of family relationships, absence from home, and isolation from school, friends and relatives. The family is the key to supporting the child through the transplant period.
- Infertility. Patients who receive autologous transplants are at risk for not being able to have children in the future. Depending on the disease being treated and the chemotherapy drugs and/or radiation therapy used for transplant, this risk can vary from very low to quite high. Sperm and egg donation and storage would be considered for any post-pubertal patients prior to the transplant procedure.
Glossary of Terms
1 Transplant: A medical treatment to replace a recipient’s diseased organ or tissues with a healthy organ or tissue from a donor
2 Donor: A volunteer (related or unrelated) who has donated stem cells for a patient
3 Chemotherapy: Treatment for cancer using chemical substances designed to kill cancer cells. It is used in large doses to help destroy a patient’s diseased marrow in preparation for a marrow transplant
4 Neuroblastoma: A solid tumor occurring in children which, in an advanced widespread stage, may be treated by autologous stem cell transplant
5 Bone Marrow: The spongy center of bones that is the “factory” for all blood cells in circulation
6 White Blood Cell: Also called a “leukocyte;” a type of blood cell produced by the bone marrow to help fight infection
7 Engraftment: Successful transplantation of donor bone marrow cells into the patient. This is shown by the growth and differentiation of donor cells to achieve normal blood counts in the recipient
8 Viruses: A type of germ that causes infections, most of which are not effectively treated with antibiotics. Examples: cytomegalovirus (CMV), herpes, varicella (chickenpox), adenovirus, hepatitis
9 Veno-Occlusive Disease: A rare condition which may occur in the first few weeks after a hematopoietic stem cell transplant (HSCT); caused by obstruction in the liver veins due to damage from chemotherapy and radiation
10 Platelet: A component of the blood important in clotting. Inadequate amounts of platelets will lead to bleeding and bruising easily
11 Red Blood Cell: A type of blood cell made in the bone marrow that carries oxygen to all parts of the bodyView full glossary