Stem cell transplant

Stem cell transplantation (SCT), also called Haematopoietic Stem Cell Transplantation (HSCT), is the replacement of a patient’s bone marrow with healthy haematopoietic stem cells.

Haematopoietic stem cells are immature cells that differentiate into red blood cells, white blood cells, and platelets.

Indications for SCT 

  1. Malignant haematology/oncology  
    1. Used when standard-dose chemotherapy is insufficient to cure the disease
    2. Chemotherapy is administered before STC to eliminate cancer cells and prepare the bone marrow by creating space for the new stem cells to engraft and grow.  Sometimes total body irradiation (TBI) is also used to destroy any remaining cancer cells and to suppress the immune system.  This helps to create a suitable environment for the donor stem cells to grow
  2. Non-malignant haematology, immunology and metabolic conditions
    1. When bone marrow fails to produce adequate blood cells or essential enzymes (Snowdon, et. al., 2022)

This resource focuses on SCT in malignant disorders in children and young people. 

Stem Cell Transplant (SCT) process – simple overview

Stem cell transplant is a treatment that replaces damaged stem cells with healthy stem cells. The process happens in three main stages:

  • A sample from the patient (usually blood) is sent to the lab to check their tissue type (HLA - Human Leukocyte Antigen type).  HLA typing determines the compatibility between the patient and potential donors. A well matched donor reduces the risk of rejection and other complications that may occur 
  • A potential donor also provide a sample for HLA testing 
  • Some patients can have a matched family donor, however if no suitable family donor is identified then international volunteer donor registries and cord blood banks will be searched. 
  • Unrelated donors and patients do not know each other’s identities. In some cases, they may be allowed to make contact after the transplant, but only if the registry deems it appropriate and the donor wishes to have contact

In simple terms: 
This stage is all about finding a good “match” so the donor’s cells will grow in the patient’s body. 

There are three main ways stem cells can be collected:

1. Peripheral Blood Stem Cells (PBSC) – the most common

  • The donor is given medication (G‑CSF) to encourage stem cells to multiply and move from their bone marrow into their bloodstream
  • The stem cells are then collected using an apheresis machine  
  • The collected cells are given fresh or frozen until needed

2. Umbilical Cord Blood

  • Stem cells are collected from the umbilical cord and placenta immediately after a baby is born
  • This poses no risk to mother or baby
  • These cells are stored in cord blood banks for future use

3. Bone Marrow Harvest  

  • Under general anaesthetic, a needle is inserted in the back of the hip bone to collect bone marrow
  • This procedure is generally safe with quick recovery, with some donors experiencing some soreness and nausea 

In simple terms: 
Stem cells come either from bone marrow, blood or from cord blood collected at birth.

  • The patient receives high‑dose chemotherapy (and sometimes radiotherapy) to remove unhealthy cells and prepare the bone marrow to receive the donor cells  
  • The healthy donor stem cells are then infused through a drip, similar to a blood transfusion 
  • These cells travel to the bone marrow and start rebuilding normal blood production—this is called engraftment 
  • During this time, the patient’s immune system is low, so they stay in strict isolation until their blood counts improve 

In simple terms: 
The patient’s own unhealthy marrow is replaced, the donor’s stem cells are given through a drip, and the patient stays isolated until their immune system starts working again.

Your role in the community

In the UK, after a child is discharged home following HSCT:

  • Post-transplant care will be led by the transplant team supported by shared care from patient’s local hospital and GP
  • Community nursing teams offer home‑based monitoring, education, early detection of complications, medication support, and act as a liaison between the family, GP, and transplant centre

These roles are supported indirectly by NHS England HSCT commissioning policies, workforce recommendations, and post‑HSCT immunisation guidelines, all of which emphasise the need for multidisciplinary collaboration involving GPs and community‑based practitioners.

Information for parents and young people

References


Birmingham Women’s and Children’s Hospital (2023) Guidelines for Immunisation of Children following High Dose Chemotherapy and HSCT. Available at: https://apps.worcsacute.nhs.uk/KeyDocumentPortal/Home/DownloadFile/1852  

Elfeky, R. et al. (2025) Workforce consensus recommendations for paediatric haematopoietic stem cell transplant centres. British Journal of Haematology. Available at: https://onlinelibrary.wiley.com/doi/epdf/10.1111/bjh.70230  

NHS England (2021) Clinical Commissioning Policy: Haematopoietic Stem Cell Transplantation (HSCT) (All Ages). NHS England. Available at: https://www.england.nhs.uk/wp-content/uploads/2022/10/Haematopoietic-Stem-Cell-Transplantation-HSCT-All-Ages.pdf  

NHS England (2025) Clinical Commissioning Policy: Haematopoietic Stem Cell Transplantation (HSCT) (All Ages). NHS England. Available at: https://www.england.nhs.uk/publication/haematopoietic-stem-cell-transplantation-all-ages/  

Snowden, J. A., Sanchez-Ortega, I., Corbacioglu, S., Basak, G. W., Chabannon, C., de la Cámara, R., et al.(2022) ‘Indications for haematopoietic cell transplantation for haematological diseases, solid tumours and immune disorders: current practice in Europe, 2022’, Bone Marrow Transplantation, 57(8), pp. 1217–1239. doi: 10.1038/s41409-022-01691-w.

Page last updated April 2026