Understanding Bone Marrow Transplant

Dr.Roshan Dikshit, 3 mins read

What is a bone marrow transplant?

A Bone marrow transplant, or BMT, is a specialized procedure that involves therapy for those who are fighting against certain types of cancer and/or other diseases. In a bone marrow transplant, cells that will otherwise be found in the bone marrow, called stem cells, are extracted or “harvested”, and then are either given back to the donor, or they are donated to another person who may require healthy stem cells. The ultimate aim of all bone marrow transplants is to transfuse (transfer) healthy bone marrow cells into a person after their own cancerous or unhealthy bone marrow has been given treatment to kill any remaining abnormal cells.

Our blood cells in their early stages are very young and are known as hematopoietic stem cells at the time. As we grow up, these stem cells mature, after which they travel out of the bone marrow and into the blood, where they grow to become red blood cells, white blood cells, and platelets.

The bone marrow is a soft and spongy tissue found inside the bones, its greatest function is serving as the place where a majority of the body's blood cells are formed and stored.

Stem cells are essentially blood cells that make other blood cells and the first stem cell we have is called the pluripotent stem cell. Stem cells are not like other blood cells in respect to some characteristics. Stem cells can renew themselves by producing more cells that are identical to them. Stem cells are also capable of generating one or more subsets of mature cells; this is called differentiation.

A bone marrow transplant is also referred to as a stem cell transplant. When bone marrow is damaged, it cannot produce enough blood cells or sufficient cells for the immune system to function properly. This is when a bone marrow transplant is required.

A bone marrow transplant can replace diseased marrow that is unable to produce its stem cells, replace stem cells that have been destroyed by chemotherapy due to cancer treatment, and it can also introduce a donor’s stem cells to help detect and kill remaining cancer cells after treatment. Others who might need to get a bone marrow transplant include people dealing with  Hodgkin’s or non-Hodgkin’s lymphoma, acute or chronic leukemia, Multiple Myeloma, aplastic anemia, Waldenstrom macroglobulinemia, Myelofibrosis, Germ cell tumors, Sarcoma, Lupus, Amyloidosis, and also for those who are receiving high doses of radiation and/or chemotherapy for treating cancer.

Bone marrow transplants have been used to successfully treat diseases like lymphomas, aplastic anemia, leukemias, immune deficiency disorders, along with other solid tumorous cancers since 1968. Today, bone marrow transplant success rates are as good as they’ve ever been, and patients can expect the procedure to go reasonably well. However, it is a major procedure in a way that it means a long recovery process, during which there will be a continuous risk of potentially serious side effects. If you’re considering how serious a bone transplant is, you can get in touch with our doctors who can talk with you about all the pros and cons of a bone marrow transplant.

Types of bone marrow transplant:

There are two primary types of bone marrow transplants; they are based on where the required stem cells come from.

There is an Autologous bone marrow transplant when your stem cells from your marrow or blood are collected by a team of surgeons and then stored while you receive treatment for cancer. After that, your stem cells are put back into your bloodstream, from where they travel to your bone marrow, establish themselves there where they can multiply and help the bone marrow produce healthy stem cells again.

In case you get stem cells from a bone marrow transplant donor after cancer treatment, it will be an allogeneic bone marrow transplant. Usually, the most suitable donors can be found among siblings and parents, there is also a national donor list from which you can look up potential donors.

In case the donor is an identical sibling whose tissue type is the same as yours, it will be called a syngeneic transplant. Doctors can also use stem cells from the blood of a newborn baby’s umbilical cord.

Preparing for a Bone Marrow Transplant 

The first step is assessing whether a candidate is suited to a bone marrow transplant procedure, this is done with physical and blood

tests and how well essential and other organs are working.

If a transplant gets the go-ahead, the type of bone marrow transplant you’ll have and what you can expect will be discussed thereafter. These decisions are usually taken by a multidisciplinary transplant committee meeting.

After the date of your transplant is fixed, you’ll need to visit the hospital a few days prior, for getting a tube called a central venous catheter inserted into a vein in the chest. This will be used by your medical team to take blood and administer medicine.

A long needle may be used to take stem cells from your marrow in the hip under anaesthesia, it’ll take about 2-3 hours and you can go home the same day. Stem cells can be directly taken from your blood as well through a procedure called apheresis, which lasts for 4-6 hours.

For an allogenic transplant, you will need to find someone with the same type of protein on their white blood cells, called a human leukocyte antigen (HLA), which runs in families usually.

Procedure:

Initially, patients are given high doses of chemotherapy in a procedure called conditioning, which lasts around ten days and

makes room for new cells to grow in the bone marrow. It’ll briefly weaken your immune system to keep the body from fighting new cells. Side effects like mouth sores, eating issues, hair loss, premature menopause, fertility complications, nausea, vomiting, and breathing or lung issues are common.

After some days of rest, new blood stem cells will be given to you through the central venous catheter, and it’s painless.

As the new cells reach the marrow, they’ll grow into red and white blood cells and platelets. This process is called engraftment and may take between 2 to 4 weeks.

Life after bone marrow transplant:

The recovery is different for everyone, but at least 3- 4 weeks of hospital stay are needed. Your immune system will be weakened and medicines will be needed to prevent infections. You might need blood transfusions and you’ll be examined by doctors regularly.

Patients can usually leave the hospital after achieving specific blood cell counts and displaying no other symptoms. The immune system can take a year or longer to recover after a transplant. You’ll need to keep visiting your doctor often and follow all advice. There is a chance of developing graft versus host disease after an allogenic transplant and your treating doctor could continuously monitor you for that.

Also, Read: What You Need to Know About Bone Cancer