Question: In what situations might a cancer patient need a stem cell transplant?
Answer: To determine if a stem cell transplant is an effective treatment option for cancer, it’s important to understand how the process works. Bone marrow is made of stem cells which produce red cells to carry oxygen to tissues, white cells to fight infections, and platelets to prevent excessive bleeding. If bone marrow is damaged or invaded by cancer, the number of healthy stem cells is significantly reduced, which can cause fatigue, bleeding and problems fighting infection. A stem cell transplant can repopulate the bone marrow and allow new stem cells to develop.
In cancers of the bone marrow or lymph nodes, high doses of chemotherapy or radiation can be the most effective treatment to kill cancer cells. However, this same treatment can also destroy healthy bone marrow, so a stem cell transplant replenishes the cells lost from the chemotherapy or radiation. This is called autologous stem cell transplantation and involves collecting the patient’s own stem cells before treatment to use as rescue after a high dose therapy.
A stem cell transplant may also be used to treat cancer directly. Stem cells from another person, typically a matched sibling, have a powerful effect in killing cancer cells. In this situation, the donated cells are transplanted to actually fight the cancer in addition to replacing the old bone marrow. This allogeneic stem cell transplantation is used for treating most forms of leukemia.
Though a stem cell transplant has great healing potential, it is not risk-free. Therefore, a patient’s care team must evaluate the benefits and risks of the transplant relative to the patient’s age, organ functions, type of cancer and status of the disease to determine if this treatment is optimal.