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Questions and answers

What is a transplant

A stem cell (bone marrow) transplant replaces a diseased blood-forming system with a healthy one.

Last updated: ~1 min read
Stem cells settle in the marrow
Figure 1.Stem cells settle in the marrow

01Short answer

In a stem cell transplant, high-intensity or reduced-intensity treatment (conditioning) first reduces the diseased marrow and leukemia cells, and then healthy stem cells are given into a vein. In an allogeneic transplant the cells come from a donor (related or unrelated); in an autologous transplant they come from the patient. In leukemia allogeneic transplants are usually used; the donor’s immune cells also fight remaining leukemia cells. It is a serious treatment with a long recovery.

02Simple explanation

A transplant is like building a “new blood factory”.

The donor’s healthy stem cells settle in the marrow and start making new blood.

03Scientific explanation

Part of the effect of allogeneic transplant is the “graft-versus-leukemia” effect; the same mechanism can cause graft-versus-host disease (GVHD).

Donors are chosen by HLA matching; related, unrelated, half-matched (haploidentical) and cord blood donors are used.

04What happens in the body?

Who it is recommended for

A transplant is discussed for high-risk acute leukemia, relapse or a poor response to treatment. The decision weighs the patient’s condition, donor availability and the risks.

The stages

Conditioning, the cell infusion, then engraftment, when the new cells take hold. Protection from infection matters most in this period.

A bridge between donor and patient
Figure 2.A bridge between donor and patient

Recovery

Recovery takes months. Regular follow-up, rebuilding immunity and watching for GVHD are needed. Support from family and a caregiver is very important.

A new marrow blooms
Figure 3.A new marrow blooms — What is a transplant

05The transplant journey

Four main stages.

Conditioning — Preparatory treatment.1ConditioningPreparatory treatment.
Cell infusion — Stem cells are infused.2Cell infusionStem cells are infused.
Engraftment — The new cells take hold.3EngraftmentThe new cells take hold.
Recovery and follow-up — Months of monitoring.4Recovery and follow-upMonths of monitoring.
New blood formationDonor cells start working.
Long supportRecovery is a team effort.

06Key points at a glance

TopicIn brief
Who it is recommended forA transplant is discussed for high-risk acute leukemia, relapse or a poor response to treatment. The decision weighs the patient’s condition, donor availability and the risks.
The stagesConditioning, the cell infusion, then engraftment, when the new cells take hold. Protection from infection matters most in this period.
RecoveryRecovery takes months. Regular follow-up, rebuilding immunity and watching for GVHD are needed. Support from family and a caregiver is very important.

07Key terms

Allogeneic
Taken from another person (a donor).
Autologous
Taken from the patient.
Engraftment
Infused cells taking hold and starting to make blood.

08Key points

  • A transplant replaces the blood-forming system.
  • In leukemia it is usually allogeneic.
  • The donor is chosen by HLA.
  • Recovery takes months.

09Frequently asked questions

Is a transplant an operation?

No, the cells are given into a vein, like a blood transfusion.

How is a donor found?

Brothers and sisters are tested first, then donor registries are searched.

10Questions for your doctor

Take these questions to your appointment. The ones you save are collected on the “My questions” page and stay on this device only.

  1. Is a transplant an operation?

  2. How is a donor found?

My questions

12Sources

  1. National Cancer Institute (NCI). Stem Cell and Bone Marrow Transplants for Cancer
  2. NHS. Stem cell and bone marrow transplants
  3. Anthony Nolan. Understanding stem cell transplants
  4. NHS. Sepsis
  5. National Cancer Institute (NCI). The Genetics of Cancer
  6. National Cancer Institute (NCI). Questions to Ask about Cancer Treatment
  7. National Cancer Institute. NCI Dictionary of Cancer Terms: remission
  8. National Cancer Institute (NCI). NCI Dictionary of Cancer Terms: blast
  9. American Cancer Society. Typical Treatment of Acute Lymphocytic Leukemia
  10. National Cancer Institute (NCI). Side Effects of Cancer Treatment
Medical disclaimerThis information is for educational purposes only and does not replace medical advice.
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