What Are the Risks of a Blood and Marrow Stem Cell Transplant?

The main risks of a blood and marrow stem cell transplant are infection, graft-versus-host disease (GVHD), and graft failure.

Infection

You can easily get an infection after the transplant because your immune system is weak. The risk of infection decreases as your immune system recovers.

You can take steps to prevent infections, such as washing your hands and staying away from crowds. Doctors use medicines to prevent and treat infections.

Transplant recipients are sometimes given vaccines to prevent viruses and infections, such as the flu and pneumonia.

Graft-Versus-Host Disease

GVHD is a common complication for people who get stem cells from a donor. In GVHD, the new stem cells attack your body.

Acute GVHD occurs within 90 to 100 days after the transplant. Chronic GVHD begins more than 90 to 100 days after the transplant or goes beyond 90 days after the transplant.

GVHD can be minor or life threatening. Signs and symptoms include:

• A rash that starts on the palms of your hands and soles of your feet and spreads to your mid-section. Over time, the rash may cover your entire body. Skin can blister or peel if the rash is very bad.
• Nausea (feeling sick to your stomach), vomiting, loss of appetite, abdominal cramps, and diarrhea. Doctors determine how bad GVHD is based on the severity of diarrhea.
• Jaundice (yellowing of the skin and whites of the eyes) and abdominal pain. These symptoms indicate liver damage.

Medicines are used to treat GVHD. Acute GVHD is treated with glucocorticoids, such as methyl prednisone, prednisone in combination with cyclosporine, antithymocyte globulin, or monoclonal antibodies.

Chronic GVHD is treated with steroids—usually cyclosporine and prednisone on alternating days.

Older people, people who have had acute GVHD before, and people who received stem cells from mismatched or unrelated donors are more likely to develop GVHD.

Doctors can reduce your chances of getting GVHD by:

• Closely matching your stem cells to your donor's through HLA tissue typing.
• Using medicines to suppress your immune system.
• Removing some types of T cells from donor cells. T cells attack your body in GVHD.
• Using umbilical cord blood as the source of donor cells.

Graft Failure

Graft failure occurs if your immune system rejects the new stem cells. It also can occur if not enough stem cells are used, the new stem cells are damaged during storage, or your bone marrow is damaged after the transplant.

Graft failure is more likely in people who receive less preparation for their transplants. People who get stem cells from poorly matched donors also are more likely to have graft failure.

Other Risks

Complications from chemotherapy and radiation treatment (used to prepare for a transplant) can occur long after a transplant. These complications may include infertility, cataracts, new cancers, and damage to the liver, kidneys, lungs, or heart.

Cancer Relapse

In some people who get stem cell transplants to treat cancer (such as leukemia), the cancer eventually comes back. This happens more often in people who use their own stem cells for the transplant (an autologous transplant) than in people who get stem cells from a donor (an allogenic transplant).

This difference occurs because stem cells received from another person recognize new cancer cells as foreign and destroy them. This is called the graft-versus-tumor effect. A person’s own stem cells don’t recognize the new cancer cells as foreign. This allows the cancer cells to grow and multiply.

Doctors use immunotherapy to help prevent and treat the recurrence of cancer in people who’ve received a stem cell transplant. Immunotherapy is treatment that stimulates the immune system to attack cancer cells.