Bone marrow transplant: who might require it?

We recently had the pleasure of speaking with leading London-based consultant haematologist, Dr Varun Mehra, who, in our latest article here, explains in detail what exactly a bone marrow transplant is and how long recovery from it generally takes.

What is a bone marrow transplant and who may need to have one?

The objective of a bone marrow (stem cell) transplant is to try to replace the diseased bone marrow and renew patient's immune system with fresh stem cells that we get either from the patient themselves or from somebody else related or unrelated that can help 

It is an effective procedure that is carried out in order to try and get rid of the disease that is affecting that patient, using strong chemotherapy and immunotherapy and infusing stem cells, which can hopefully provide a better life and a new chance to be able to beat that underlying blood cancer/marrow disease that they are suffering from.

It is designed for patients who have very complex types of malignant blood cancers (such as leukaemia, lymphoma, and myeloma) and non-malignant conditions such as autoimmune diseases (multiple sclerosis, Crohn's disease, systemic sclerosis) and bone marrow failure conditions (aplastic anaemia) that are not otherwise treatable with standard drug therapies, and this transplant provides a potential cure/long-term disease control for those conditions.

What happens during a bone marrow transplant procedure?

A procedure of stem cell transplant is very much dependent on what type of transplants we're doing. There are two distinct types of these transplants, with the most common one being autologous transplants. This requires stem cells from the same patient collected beforehand and then admitting these patients for getting through a certain amount of chemotherapy to try and kill that diseased bone marrow, and to then try to get the stem cells back in again.

This is also known as stem cell rescue treatment, in which we are rescuing them from very strong chemotherapy by virtue of giving stem cells back to them as a rescue treatment option. This allows the bone marrow to grow back again, producing normal blood cells which hopefully leads to the maintaining of a long-term disease free period. 

In autoimmune conditions, these autologous stem cell transplants act to ‘reset’ the defective immune system that is reacting against our own cells, and therefore improves tolerance of the immune system again without causing further damage. This allows reducing further organ dysfunction and functional recovery in some cases.

The most successful example is transplants in Multiple Sclerosis patients, with durable responses seen in up to 70-75 per cent of patients who have otherwise failed previous therapies. Allogeneic stem cell transplants, i.e. receiving stem cells from a different person, is a more complex procedure and requires expertise in managing the complexities associated with such procedures. This procedure provides a potential long-term cure for some of the difficult-to-treat/aggressive blood cancers and bone marrow failure conditions.

What does recovery time look like?

You will need to be admitted into hospital  to receive stem cell transplant. A drip of either freshly donated or previously frozen stem cells goes through peripheral blood in your arm after a period of chemotherapy, and you have to stay in hospital for a few weeks to recover from that treatment. The chemotherapy itself is quite toxic and can unfortunately result in quite a lot of side effects. However, with stem cells going back in, it allows the bone marrow to recover quickly and have a successful recovery in a few weeks.

However, it is important to stress here that the recovery period can be different for different individuals, depending on their fitness levels, for example, and how they cope through those chemotherapies and what side effects they have. The majority of patients go home by the end of the third or fourth week after the transplant, but they require close follow-up as an outpatient to manage any medium to long-term complications post-transplant. 

What results can patients expect after undergoing this procedure?

Several factors play a role in potential outcomes following stem cell transplants, and patients are counselled in detail about the individual risks and benefits of doing such a procedure. The hope is to provide them with the most effective and least complicated way of doing these procedures to achieve long-term remission (disease control) or cure from underlying conditions.

Some patients may suffer from complications and may require expertise from physicians experienced in performing stem cell transplants in managing such problems. In terms of allogeneic stem cell transplants for malignant conditions, we generally say about 50 percent of our patients can potentially be cured from the underlying disease, if we were to do stem cell transplants in the correct and safe way. For patients with bone marrow failure, up to 90 percent of patients can expect to be cured.

How are bone marrow doners found and selected?

If there are no available related donors in the family, a third of patients may not find a suitable donor, depending on ethnicity, and thus, there is an increased need to identify suitable donors from ethnic minorities and mixed ethnicities. Most people intending to be stem cell donors only need to provide a small tissue sample, which will be either a swab in your mouth or sometimes a blood sample.

The samples are tested for the specific HLA type (genetic traits) and matched with potential patients, in need of an allogenic stem cell transplant. There are number of national and international stem cell donor registries that offer to test and register donors for free, and often run local campaigns to boost registrations.

We look for those voluntary donors in those registries to see if they match with our patients in the correct way and then approach them for donation. The matching exercise is quite detailed, as it involves comprehensive independent checks to select the right donor. We make sure that they understand what they are signing up for and explain the donation procedure, which is very straightforward, performed using simple stem cell collection techniques directly from the blood stream, and requires minimum time from the donor with no effect on their long-term health.

Dr Varun Mehra is a highly esteemed consultant haematologist who specialises in bone marrow transplants. If you are due to undergo one in the near future, be sure to contact Dr Mehra today via his Top Doctors profile to ask any questions that you may have.