Collecting stem cells

You might have a stem cell or bone marrow transplant as part of your treatment for non-Hodgkin lymphoma (NHL). Part of this process is collecting the stem cells. The stem cells are collected from the bloodsteam or the bone marrow.

Types of transplant

When you have your own stem cells collected this is part of an autologous transplant. 

Having stem cells from a donor is part of an allogeneic transplant.

Collecting your own stem cells

This is called a stem cell collection or harvest.

Preparing for your collection

Before your stem cell collection (harvest) you have injections of a growth factor.

Growth factors are natural proteins that help the bone to make blood cells. You have them as small injections just under the skin. They make your bone marrow produce more stem cells so they spill out into the blood. 

You have the daily growth injections for about 5 days before you have your stem cell collection. Sometimes you also have injections after your transplant. The injections are called G-CSF. 

After your growth factor injections you have blood tests every day until you have enough stem cells in your blood for collection.

On collection day

You might have your stem cells collected each day for 2 or 3 days. This is to collect enough stem cells.

The collection takes about 3 or 4 hours each time.

You lie down on a couch. The nurse puts a drip into each of your arms and attaches the drip to a machine. Your blood passes out of one drip, through the machine, and back into your body through the other drip. The machine filters the stem cells out of your blood.

The stem cells are frozen until you are ready to have them back after high dose chemotherapy.

Side effects of a stem cell collection

You might feel very tired after having your stem cell collection. You might have:

  • tingling around your mouth
  • muscle cramps

This happens if your calcium level gets low during your collection. You have extra calcium through a drip if this happens.

Collecting stem cells from your bone marrow

Collecting bone marrow is called a bone marrow harvest.

What happens

You have this procedure in theatre and you have a general anaesthetic. This means you are in a deep sleep during the procedure.

The doctor puts a needle through the skin into your hipbone (pelvis) to remove bone marrow. Your doctor draws the bone marrow through a needle and into a syringe.

To get enough marrow the doctor usually puts the needle into several different parts of the pelvis. Occasionally, doctors use the breast bone (sternum) as well. The doctor removes about two pints of bone marrow and freezes it.


When you wake up, you have up to 6 puncture sites covered with dressings. You will feel very bruised and sore. This can last for up to a week, but painkillers can help.

You usually stay in hospital overnight after a bone marrow harvest. This is to make sure you have recovered from the anaesthetic. You might also need a blood transfusion afterwards. 

Collecting stem cells from a donor

Instead of collecting your own stem cells, you might have a transplant using stem cells from a donor. This is called an allogeneic transplant. 

Your donor has growth factor injections in preparation for a stem cell harvest. They have a similar procedure to people with cancer who have their own stem cells or bone marrow collected.

Having a transplant

After your stem cell collection, you have high dose chemotherapy and you might have radiotherapy. These treatments aim to kill any NHL cells that are left in your body.

You then either have you own stem cells back, or the stem cells of your matched donor. You have these through a drip  into your central line and into your bloodstream. 

Last reviewed: 
04 Jan 2021
Next review due: 
04 Jan 2024
  • Non Hodgkin lymphoma: diagnosis and management (NG52) 

    National Institute for Health and Care Excellence (NICE), 2016

  • Indications for Autologous and Allogeneic Hematopoietic Cell Transplantation: Guidelines from the American society for Blood and Marrow Transplantation 

    N Majhail and others 

    Biology of Blood and Marrow Transplantation, 2015. Volume 21, Issue11, pages 1863–1869

  • Hematopoietic stem cell tranplantation in Europe 2014: more than 40 000 transplants annually

    JR Passweg and others  

    Bone Marrow Transplant, 2016. Volume 51, Issue 6, pages 786-792

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