In an autologous transplant, a patient’s own blood stem cells are removed from bone marrow or peripheral blood in the weeks before treatment. These cells are frozen and stored while the patient gets treatment (high-dose chemotherapy and/or radiation) and then infused back into the patient’s bloodstream by IV. This is a common type of transplant for certain types of cancer, including multiple myeloma and non-Hodgkins lymphoma.
How are the stem cells collected?
A bone marrow transplant is done by transferring stem cells from one person to another. Stem cells can either be collected from the circulating cells in the blood (the peripheral system) or from the bone marrow.
Peripheral blood stem cells. Peripheral blood stem cells (PBSCs) are collected by apheresis. This is a process in which the donor is connected to a special cell separation machine via a needle inserted in arm veins. Blood is taken from one vein and is circulated though the machine which removes the stem cells and returns the remaining blood and plasma back to the donor through another needle inserted into the opposite arm. Several sessions may be needed to collect enough stem cells to ensure a chance of successful engraftment in the recipient.
A medicine may be given to the donor for about one week prior to apheresis that will stimulate the bone marrow to increase production of new stem cells. These new stem cells will be released from the marrow and into the circulating or peripheral blood system; from there they can be collected during apheresis.
Bone marrow harvest. Bone marrow harvesting involves collecting stem cells with a needle placed into the soft center of the bone, the marrow. Most sites used for bone marrow harvesting are located in the hip bones and the sternum. The procedure takes place in the operating room. The donor will be anesthetized during the harvest and will not feel the needle. In recovery, the donor may experience some pain in the areas where the needle was inserted.
If the donor is the person himself or herself, it is called an autologous bone marrow transplant. If an autologous transplant is planned, previously collected stem cells, from either peripheral (apheresis) or harvest, are counted, screened, and ready to infuse.