Decision to transplant
The medical staff will make a decision to offer a blood or marrow transplant to a patient depending on a number of factors. Blood cancers such as leukaemia, myeloma, lymphoma and a few non-cancerous conditions such as aplastic anaemia are the conditions most likely to be the underlying reason for a blood or marrow transplant.
Identification of a donor
Blood is taken for tissue typing from the patient and family members – usually siblings (there is a 1 in 4 chance of them being a match) and laboratory checks are carried out to see if there is a match between the potential donor and the recipient.
If there is no family member available or no match with the patient then there is an unrelated donor search which takes place with registries who have databases of tissue typing of potential donors. The following are British registry website addresses.
The British Bone Marrow Registry
The Anthony Nolan Bone Marrow Registry
This is a website that encourages people from non-white ethnic groups to volunteer to become a donor. There is a reduced chance of finding a suitable match due to reduced numbers of donors registering from a non- white ethnic background.
The African Caribbean leukaemia trust
Donor and patient assessment
Once a patient has a match then plans are made for the transplant. The donor and patient will need medical assessment checks.
Harvest of cells
The donor will need to have their cells harvested. If it is stem cells this can be done through an Apheresis unit and can take about 4 hours.
The bone marrow harvest takes place in a hospital operating room, usually under general anesthesia. It involves little risk and minimal discomfort. There are no surgical incisions or stitches involved – only skin punctures where the needle was inserted. The amount of bone marrow harvested only represents about 2% of a person’s bone marrow which the body can replace in four weeks.
In order to make it easier to give medication, to take blood samples and to give the patient blood products a central line will be inserted in a large vein. This is often known as a Hickman line (after the inventor). This is positioned under local anaesthetic and a sedative can also be given if wished. The fine, flexible, plastic tube goes under the skin of the upper chest and comes out a few inches below the collar bone.
It is useful to leave the line in place for 3-4 months after transplant so that blood tests and any therapy needed after transplant may be given with minimal discomfort. As it is a potential source of infection the nursing team will take extra care with looking after it whilst the patient is in hospital. Full advice will be given on how to care for it once the patient has a plan to go home and again they will not be expected to look after it if not feeling confident doing so.
If a double lumen line is already in place and this is working well then it will remain. However, if the patient has a single lumen line this needs to be removed and a double lumen line inserted instead. This is because a single lumen line is not able to carry the volume of fluids and drugs necessary during a transplant.
The patient will go through conditioning before the transplant – chemotherapy or radiotherapy to destroy the cancer cells and suppress the immune system so that the body doesn’t reject the transplanted cells.
There are many side effects of the conditioning – nausea, vomiting, diarrhoea, hair loss, mouth sores and ulcers, infections, bleeding, anaemia, infertility, fatigue, cataracts, secondary cancers. Which of these the patient will get will vary according to the conditioning regime and the patient’s genetic make up, they may get very little or they may have serious side effects.
There is a new kind of stem cell transplant called a “reduced intensity conditioning transplant” or RIC-transplant. As the name implies it uses less intense conditioning and doesn’t rely on all the cancer cells being killed immediately at the time of transplant. Instead it relies on the donor’s immune system to fight the cancer cells. This is used as an alternative to a standard transplant. It may be particularly valuable in patients who have other health problems or who have had a great deal of chemotherapy or even a previous transplant.
The patient receives the stem cells within a day or so of the conditioning and they are given through a central line, much the same way as a blood transfusion is given.
The cells start to grow and develop into mature blood cells, called engraftment; this may take 2 to 4 weeks. The patient may be in hospital for 5 to 6 weeks and most of that will be in isolation as the patient is very vulnerable to infection at this time as the blood count is low.
After your transplant your chimerism will be checked regularly by a blood test. Full donor chimerism means that 100% of bone marrow and blood cells are of donor origin, while mixed or partial chimerism means that the patient’s cells are also present.
At day 100 post transplant you will have a bone marrow biopsy to confirm your remission status.
Your blood group will change after your blood or marrow transplant as yours will become the same as the donor’s blood group (unless it was the same as yours anyway in which case it will stay the same).
Post transplant patients are at risk of transfusion-associated GvHD and should a blood transfusion ever be required, then the transfused blood components MUST BE Gamma Irradiated.
Please see this NHS leaflet for more details which is available in hard copy in the ward and in the day care unit.
There is more in-depth information on what having a blood or marrow transplant involves, please go to this NHS website.
This is an American site but it does have very good information on it.
This is Cancer Research UKs information on bone marrow transplant