Bone marrow transplant (BMT)/ Stem cell transplant
The procedure of replacement of a diseased, damaged, or nonfunctional bone marrow with healthy blood cells forming stem cells is a Bone marrow transplant or stem cell transplant.
Bone marrow transplant or stem cell transplant is needed in case bone marrow stops working and is not able to produce enough healthy blood cells. Bone marrow transplants can be done with cells from the patient’s own body(autologous transplant) or from a donor (allogeneic transplant).
Types of bone marrow/stem cell transplant
Allogeneic stem cell transplant (from the patient)
Autologous stem cell transplant (from the donor)
Reason for BMT
A bone marrow or stem cell transplant may be done for:
Damage to the bone marrow as a result of high doses of chemotherapy or radiation for cancer treatment by replacing or rescuing the bone marrow.
Diseased marrow replacement with new stem cells
Some cancers where new stem cells, kill cancer cells directly
Bone marrow transplants is a viable and proven treatment method for a number of cancerous and non cancerous conditions which are otherwise refractory to other treatment methods. These conditions include:
Acute Leukemia or most common childhood blood cancer.
Adrenoleukodystrophy – a rare genetic disorder.
Aplastic anemia – inability to produce sufficient blood cells.
Bone marrow failure syndromes – genetic blood disorder with associated aplastic anemia component.
Chronic Leukemia – bone marrow is hyperactive and produces too many lymphocytes (a type of white blood cell) as a result production and function of other blood cells.
Hemoglobinopathies – a group of genetic blood disorders and diseases that causes abnormal structure of the globin chains of the hemoglobin in the red blood cells.
Hodgkin’s lymphoma – a cancer of specific type of white blood cells.
Immune deficiencies – disease of white blood cells that help fight infections.
Inborn errors of metabolism – inherited disorders causing improper management of nutrition absorption, consumption and storage.
Multiple myeloma- cancer developing in plasma cells, a type of white blood cells.
Myelodysplastic syndromes – Blood cells in the marrow do not reach maturity, hence functionally deficient.
Neuroblastoma – Cancer if nerve tissue.
Non-Hodgkin’s lymphoma – cancer of the lymphatic system.
Plasma cell disorders puts patient at higher risk.
POEMS syndrome – Damages the nerves and other tissues causing weakness and loss of motor power.
Primary amyloidosis – antibody-producing cells does not function properly and produce abnormal protein fibers that gets deposited in various organs and tissues
Risks associated with bone marrow transplant
A stem cell or bone marrow transplant can cause multiple complications in a wide range of spectrum from minimal or very mild to serious complications that may require treatment or hospitalization or even ICU care. At times life-threatening complications can also occur. Risk to a particular patient depends upon multiple factors, few of which may be basic disease causing need for BMT, severity of disease, general health condition, functioning of other organs, age of the patient and type of transplant.
Complications from a bone marrow transplant may be:
Graft-versus-host disease in allogeneic transplant.
Stem cell Transplant (graft) failure.
Early onset Cataracts
A bone marrow transplant doctor after complete thorough assessment can explain risk of complications from a bone marrow transplant. A well informed decision can be taken up after weighing the risks and benefits.
Graft-versus-host disease(GVHD): When the Immune cells of the donor fight against the recipient.
There is a risk of developing graft versus host disease in case of an allogeneic bone marrow transplant. It is due to an offensive launched by the grafted or transplanted immune cells of the donor against the already immuno-compromised recipient. The immune cells from the donor identifies the host cells and tissues as foreign.
GVHD risk is higher if the donor is not related by blood to the patient. Stem cells from first degree blood relatives have the least risk. GVHD can occur anytime after a Bone marrow Transplant. Many people who have an allogeneic transplant get GVHD at some point of time. GVHD can happen to anyone who gets a bone marrow transplant from a donor except in case if the donor is an identical twin sibling.
Graft versus host disease are two types:
Acute GVHD occuring in the first few months after the stem cell transplant. It affects the skin, liver and the digestive tract.
Chronic GVHD develops later or much later and can affect multiple organs. Symptoms can be varied and are not immediately life threatening. These are usually joints or muscle pain, breathing difficulty, change in vision, drying of eyes, skin rash, skin scarring, jaundice, dring of mouth with sores, loose stools and nausea or vomiting
Bone Marrow Transplant procedure
Tests and procedures
A number of tests and other procedures are done to assess general health and pre-transplant condition, and to ensure safety and minimise the risk associated with the transplant. This may take upto few days.
A long catheter called intravenous line is inserted into a large vein in the neck or chest. This catheter is the route for transfusion of stem cells for BMT, medications, fluids and blood into the patient’s body.
Autologous stem cell transplant
In case of autologous stem cell transplant, the patient undergoes apheresis, a process to separate and collect stem cells from blood. Prior to this for a few days stem cell production and its circulation in blood is boosted with daily injections of growth factor. Blood from the patient is drawn from a vein and passed through a machine that separates the stem cells from rest of the blood during the process of apheresis. The collected stem cells are frozen and preserved for transplant later. Rest of the blood is transfused back into the patient.
Collecting stem cells for allogeneic transplant
When patients’ own stem cells are not sufficient or suitable due to disease process a donor is needed for allogeneic transplant. A donor once identified and confirmed, stem cells from the donor are harvested.
Stem cells from a donor can be collected from blood or bone marrow. It is a transplant team’s decision what suits best in a particular condition.
Cord blood stem cell transplant is another type of allogeneic transplant. Another type of allogeneic transplant uses stem cells from the blood of umbilical cords (cord blood transplant). At the time of birth mothers may permit to donate cords of their babies. Blood from these cords is extracted and frozen and stored in a cord blood bank for future bone marrow transplant.
Once the tests and procedures are done and found suitable for BMT, a process called conditioning is started. This involves chemotherapy and may be radiotherapy as well. Conditioning is done in order to:
Suppress recipients immune system
Eliminate cancer cells in case of leukemia
Readying bone marrow to receive the new stem cells
Conditioning process usually involves chemotherapy, radiotherapy or both. It depends upon the underlying disease condition, which type of conditioning process needs to be done. It also depends on disease activity, status, general health condition and type of transplant planned. Conditioning usually causes side effects which may include:
Digestive tract disturbances such as
Mouth sores or ulcers
Infertility or sterility
Other complications, such as heart, liver or lung failure
Medications and other measures can be done to reduce these side effects.
If the age or health of the recipient doesn’t permit, reduced intensity conditioning is done. This usually involves lower doses of radio or chemotherapy.
Purpose of this type of conditioning is to suppress the immune system so as to prevent rejection of transplanted stem cells. In the process some of the cancerous cells are also killed but not all. Transplanted stem cells then over time replace the cells in the recipients. Immune factors in these stem cells then fight the cancer cells.
During bone marrow transplant
After the conditioning is complete or satisfactory, stem cells from the donor/ or frozen autologous stem cells are transfused through the central line.
Bone marrow transplant infusion is a painless process. No anesthesia is needed for the bone marrow transplant. Patient stays awake during the procedure.
After bone marrow transplant
Transplanted stem cells after infusion through the central line, travels through the blood and enters the bone marrow, where they get deposited. In some time they multiply and produce new blood cells. This process of graft uptake and multiplication is called engraftment. Normally it takes several weeks before the bone marrow is able to produce blood cells to the normal level.
During the follow-up period regular check-ups and blood tests may be needed to monitor a patient’s condition and progress. Close medical supervision is required for a few days after the BMT. In case of any signs of complication or infection, the patient may need to be treated with hospitalisation.
After bone marrow transplant, the recipient must remain under close medical care for a few weeks. If there are any signs of infection or other complications, the recipient may need to stay in the hospital for several days or sometimes longer. Patients have to stay near the hospital for a few weeks or months after the transplant, to allow for close monitoring. Length of stay usually depends on the type of transplant and possibility of complications.
Time to time blood or its component transfusions may be needed in the post- transplant period till patients’ own bone marrow starts producing enough cells.
A BMT patient remains at a higher risk of infections for months or years after the transplant. Regular life-long follow-up is done to look for any signs of infection at the earliest.
In case of an allogeneic BMT from a donor, medications are needed not only to prevent graft versus host disease (GVHD) but also to suppress recipients immune system with immunosuppressive medications to prevent destruction of grafted stem cells.
Till the recovery of the recipient’s own immune system, medications to prevent infections are given.
Diet and lifestyle
Diet and lifestyle especially after the BMT period plays a crucial role in transplants success and its maintenance. After the transplant patient must adjust to a well balanced healthy diet. Dieticians can advise about a diet which can not only prevent excessive weight gain after the stem cell transplant but also to control the side effects induced by the medications, chemotherapy and other complications.
Some common dietary recommendation are:
Eating fresh foods to prevent intestinal infections
Well balanced diet with wide variety of vegetables, fruits, lean meats, whole grains, healthy unsaturated fats.
Limited salt intake
Alcohol and smoking restrictions
Grapefruit and its juice interferes with their interference on immunosuppressive medications
Regular physical activity after a bone marrow transplant helps control weight, blood pressure, blood sugar, increases strength and endurance.
Prevention of cancer after a stem cell transplant is very important. Important measures include:
Regular cancer screening
Results and recovery after Bone Marrow Transplant
Purpose of a bone marrow transplant is to cure the disease, improve quality and quantity of life. BMT in most cases causes either remission or complete cure to disease.
Most people go through the process of bone marrow transplant with very few side effects and complications. Whereas others experience multiple problems, in both short and long terms. Course , after a bone marrow transplant varies from person to person and is usually difficult to predict beforehand.
Most recipients even with significant complications during and after stem cell transplant ultimately return to normal activities and significantly improved quality of life.
Survival rates after Bone marrow Transplant
Survival after a bone marrow transplant depends on multiple factors, most of which depends on the recipient. These include:
Underlying disease causing need for transplant
Severity of the disease
Duration of disease
Stage of cancer
Availability of donor
In general survival of patients with non malignant disease is much better with 70%-90% survival in a matched sibling compared to 35%-65% survival in an unrelated donor.
Cost of Bone Marrow Transplant
Bone marrow transplant is a complicated procedure and more so needs complex world class infrastructure to prevent infection and maximise the chances of success.
Cost of BMT varies greatly the world over and also depends upon the type of bone marrow transplant. Autologous BMT costs less than the allogeneic BMT.
India is the most cost-effective place to get a stem cell/bone marrow transplant costing a fraction when compared to western countries. In India the starting cost of a BMT is around USD 20000, whereas the same treatment in the USA would cost upwards of USD 200,000. Result and success rate of BMT in India is as good as in western countries, thanks to world-class infrastructure, a number of JCI accredited hospitals, and well qualified, trained, and extensively experienced doctors.