What are the risks of an allogeneic stem cell transplant?

Early complications usually occur within 5 to 10 days and include:

• Mouth sores.
• Hair loss.
• Bleeding, because of severe reduction in red blood cells, white blood cells and platelets.
• Nausea and vomiting.
• Diarrhea.
• Infection, such as pneumonia, shingles, or herpes simplex.

Other possible complications include:

• Depression.
• Infertility.
• Cataracts.
• Kidney, lung and heart complications.
• Recurrence of the disease that the transplant was used to treat.
• Other cancers.

Serious, long-term complications include:

• Graft failure. The new stem cells do not work, or they work for a short time and then fail. If this occurs, the likelihood of a cure is low.
• Graft-versus-host disease (GVHD). The new stem cells attack other cells in your body. If it happens within 3 months, it is called acute GVHD. If it happens after 3 months, it is called chronic GVHD. After chronic GVHD develops, it may take as long as 3 years to go away. GVHD affects the skin, gastrointestinal tract and liver. It can cause death. GVHD is treated with medicine that lowers the activity of your immune system. GVHD does not occur when an identical twin is the donor.
• Veno-occlusive disease. This is a serious liver problem caused by the high dose of chemotherapy or radiation given before a transplant. Symptoms include swelling and tenderness of the liver, weight gain, jaundice, and fluid buildup in the belly.
• Infections.