Internal Medicine Department
Hematology Division

The Stem Cell Transplant Process

The stem cell transplant process depending on the type of transplant, the disease requiring transplant, and your tolerance for certain medications.

  • Most often, high doses of chemotherapy and/or radiation are included in the preparations. This intense therapy is required to effectively treat the malignancy and make room in the bone marrow for the new cells to grow. This therapy is often called ablative, or myeloablative, because of the effect on the bone marrow. The bone marrow produces all the blood cells in our body. Ablative therapy prevents this process of cell production and the marrow becomes empty. An empty marrow is needed to make room for the new stem cells to grow and establish a new production system.
  • After the chemotherapy and/or radiation is administered, the marrow transplant is given through the central venous catheter into the bloodstream. It is not a surgical procedure to place the marrow into the bone, but is similar to receiving a blood transfusion. The stem cells find their way into the bone marrow and begin reproducing and establishing new, healthy blood cells.
  • Supportive care is given to prevent and treat infections, side effects of treatments, and complications. This includes frequent blood tests, close monitoring of vital signs, strict measurement of input and output, daily weigh-ins, and providing a protected and sterile environment.

The days before transplant are counted as minus days. The day of transplant is considered day zero. Engraftment and recovery following the transplant are counted as plus days. For example, a patient may enter the hospital on day -8 for preparative regimen. The day of transplant is numbered zero. Days +1, +2, etc., will follow. There are specific events, complications, and risks associated with each day before, during, and after transplant. The days are numbered to help the patient and family understand where they are in terms of risks and discharge planning.
After infusion, the patient may spend several weeks in the hospital. After leaving the hospital, the recovery process continues for several months or longer, during which time the patient cannot return to work or many previously enjoyed activities. The patient must also make frequent follow-up visits to the hospital or physician's office.

When does engraftment occur?


Engraftment of the stem cells occurs when the donated cells make their way to the marrow and begin reproducing new blood cells. Depending on the type of transplant and the disease being treated, engraftment usually occurs around day +15 or +30. Blood counts will be performed frequently during the days following transplant to evaluate initiation and progress of engraftment. Platelets are generally the last blood cell to recover.   Engraftment can be delayed because of infection, medications, low donated stem cell count, or graft failure. Although the new bone marrow may begin making cells in the first 30 days following transplant, it may take months, even years, for the entire immune system to fully recover.

What complications and side effects may occur following BMT?

Complications may vary, depending on the following:

  • type of marrow transplant
  • type of disease requiring transplant
  • preparative regimen
  • age and overall health of the recipient
  • variance of tissue matching between donor and recipient
  • presence of severe complications

The following are complications that may occur with a bone marrow transplantation. However, each individual may experience symptoms differently. These complications may also occur alone, or in combination:

Infections
Infections are likely in the patient with severe bone marrow suppression. Bacterial infections are the most common. Viral and fungal infections can be life threatening. Any infection can cause an extended hospital stay, prevent or delay engraftment, and/or cause permanent organ damage. Antibiotics, anti-fungal medications, and anti-viral medications are often given to prevent serious infection in the immunosuppressed patient.
    
Low platelets and low red blood cells
Thrombocytopenia (low platelets) and anemia (low red blood cells), as a result of a non-functioning bone marrow, can be dangerous and even life threatening. Low platelets can cause dangerous bleeding in the lungs, gastrointestinal (GI), and brain.
    
Pain
Pain related to mouth sores and gastrointestinal (GI) irritation is common. High doses of chemotherapy and radiation can cause severe mucositis (inflammation of the mouth and GI tract).
    
Fluid overload
Fluid overload is a complication that can lead to pneumonia, liver damage, and high blood pressure. The primary reason for fluid overload is because the kidneys cannot keep up with the large amount of fluid being given in the form of intravenous (IV) medications, nutrition, and blood products. The kidneys may also be damaged from disease, infection, chemotherapy, radiation, or antibiotics.
    
Respiratory distress
Respiratory status is an important function that may be compromised during transplant. Infection, inflammation of the airway, fluid overload, graft-versus-host disease, and bleeding are all potential life-threatening complications that may occur in the lungs and pulmonary system.
    
Organ damage
The liver and heart are important organs that may be damaged during the transplantation process. Temporary or permanent damage to the liver and heart may be caused by infection, graft-versus-host disease, high doses of chemotherapy and radiation, or fluid overload.
    
Graft failure
Graft failure is a potential complication. Graft failure may occur as a result of infection, recurrent disease, or if the stem cell count of the donated marrow was insufficient to cause engraftment.
    
Graft-versus-host disease
Graft-versus-host disease (GVHD) can be a serious and life-threatening complication of a bone marrow transplant. GVHD occurs when the donor’s immune system reacts against the recipient’s tissue. The new cells do not recognize the tissues and organs of the recipient’s body. The most common sites for GVHD are GI tract, liver, skin, and lungs.

What is the long-term outlook for a bone marrow transplantation?

Prognosis greatly depends on the following:

  • type of marrow transplant
  • type and extent of the disease being treated
  • disease response to treatment
  • genetics
  • your age and overall health
  • your tolerance of specific medications, procedures, or therapies
  • severity of complications

As with any procedure, such as bone marrow transplant, prognosis, and long-term survival can vary greatly from person to person. The number of transplants occurring for an increased number of diseases and medical developments has greatly improved the outcome for bone marrow transplant in children and adults. Continuous follow-up care is essential for the patient following a bone marrow transplant. New methods to improve treatment and to decrease complications and side effects of a bone marrow transplant are continually being discovered.