Better quality life with stem cell transplant

by Samangie WETTIMUNY

[email protected]

Dr. Anslem Lee, Consultant Paediatric Haematologist and Oncologist at Parkway Cancer Centre, Singapore and Dr. Desmond Wai, Consultant Transplant Hepatologist and Gastroenterologist of the Asian Centre for Liver Diseases were in Sri Lanka recently to attend the scientific session of Sri Lanka College of Physicians. At an exclusive press meet held for the media at the Cinnamon Grand, Colombo, the two internationally recognized specialists briefed the media on both liver transplant and Stem Cell transplant. The press conference was organized by the Parkway Group Healthcare Country Manager, Shuvo Hridayesh.

Basically blood diseases and cancer in children are quite different from those of adults. Adults normally get anaemia, leukaemia and other cancers. "For children anaemia is mostly congenital. Some of them are quite serious and the children may not be able to survive into the adulthood unless they undergo special treatment. The types of cancer seen in children are also very different from those of adults. The types such as lung or breast cancers almost never occur in children" says Dr. Anslem Lee, Consultant Paediatric Haematologist, Parkway Cancer Centre, Singapore. "Even if they occur in children, that do happen in very unusual situations."

Most of the cancers seen in children (0-18 years)are leukaemia, brain cancers and Lymphomas. If you give the same treatment to both adults and children they respond very differently. That is why we need specialists to look after children with blood diseases and cancer.

Leukaemia is a type of cancer that affects the bone marrow and lymphatic tissues. All cancers begin in cells which make up blood and other tissues. Normally cells grow and divide to form new cells as and when the body needs them. When cells grow old, they die, and new cells take their place. Sometimes this orderly process goes wrong. New cells form when the body does not need them, and the old cells do not die when they should. This is known as leukaemia where the bone marrow produces abnormal white blood cells that eventually crowd out other cells. When it comes to children it is very rare to see a child born with leukaemia. Most of the leukaemia cases occur between 2-5 years of age. "Anyway we have seen leukaemia in much younger children as well. Recently I just found a six month year old baby suffering from leukaemia. But it is very uncommon to see a baby below one year having leukaemia"

Earlier incurable or possible fatal blood disorders such as multiple myeloma, chronic lymphatic leukaemia and thalassaemia Major cannot be cured by chemotherapy and or radiotherapy. But in recent years, there have been a breakthrough in the field of haematology and stem cell transplant that offer new therapies which help patients live longer and lead better lives.

Stem cell transplantation has a very wide and powerful application among the special treatments for blood diseases and cancer. Stem cell transplantation (It was earlier called Bone Marrow Transplantation) is one of the special treatments for blood diseases and cancer. "Stem cell transplantation is the first form of transplantation we did for children with blood diseases and cancer.

Stem Cell transplantation

A stem cell transplant allows a patient to be treated with high doses of drugs, radiation or both. The high doses destroy both leukaemia cells and normal blood cells in the bone marrow. Later the patient receives healthy stem cells.

If this is a congenital disease of the bone marrow like thalassaemia, all the thalassaemia cells are removed by drugs together with other normal bone marrow cells and a normal bone marrow from another individual will be transplanted. New blood cells develop from the transplanted stem cells. The patient then recovers from the illness. This is the principle of bone-marrow transplantation. What we replace are the stem cells inside the bone marrow, not actually all the bone marrow cells. These stem cells develop into different blood cells (red blood cells, white blood cells and platelets).

Stem cells are usually obtained from another individual. Then it is called an allogenic transplant. But sometimes we get the stem cells from the patient himself and such types of transplantations are called autologous transplant. When we use the stem cells of another individual we use it for patients suffering from leukaemia because we need the stem cells of the donor not just to replace the bone marrow, but also to hit on the leukaemia cells.

When we treat thalassaemia (when the patient's bone marrow is basically carrying the disease) we need to use another individual's stem cells to correct this congenital disease. So allogenic has a very wide application from leukamia to genetic disorders etc.

We use autologogus stem cells in children for treatment of some cancers. The most common condition is as a treatment for neuro plastoma. Neuro plastoma is a special cancer in children which you almost never come acrossin adults.

This is a very aggressive type of cancer. If we use chemotherapy the chance of curing neuro plastoma is only 10%. Nowadays we use chemotherapy and Stem cell transplantation, using the patient's own stem cells for transplantation. We can increase the cure rate to 40 %. It is indeed a massive improvement.

We also use stem cell transplant for other special cancers in children, like muscle cancers or even brain cancers. For all these we can use patient's own stem cells.

Donor's age is not a problem. But if the donor is very young and the recipient is a grown-up, it may be difficult as the donor may not have enough stem cells for transplant." The youngest donor from whom we got stem cells is just one year old. The patient was 4-5 years old. Actually he was the donor's brother.

In general the donor is very safe, the risk is 0.1% for the donor. (depending on the situation)

Other forms of treatments

Most patients with leukaemia and other blood diseases receive chemotherapy. This type of cancer treatment uses drugs to kill leukaemia cells. Depending on the type of leukaemia, the patient may receive a single drug or a combination of two or more drugs.

Radiation therapy uses high energy rays to kill leukaemia cells. For most patients, a large machine directs radiation at the spleen, the brain, or other parts of the body where leukamia cells may have collected.

(Dr. Anslem Lee helped establish the paediatric bone marrow transplantation (BMT) programme at the Queen Mary Hospital, Hong Kong. He performed the first BMT for thalassaemia. In 1994, Dr. Lee performed the first case of umbilical cord blood transplantation in Hong Kong. )

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What are haematopoietic stem cells?

Stem cells are blood cells at the earliest stage of development in the bone marrow. Within the bone marrow, stem cells develop into different blood cells (red blood cells, white blood cells and platelets).

When cells fully mature, they are released into blood stream. Normally , most of the stem cells in the body are in the bone marrow and there are only very small numbers in the blood stream.

However, it is possible to stimulate the stem cells to move into the bloodstream using injections of a special protein known as growth factor. Blood stem cells can be collected from the bone marrow or bloodstream. They are progenitors or "Mother of all Blood Cells' and have the ability to produce specialised cells and reproduce themselves.

Sources of haematopoietic stem cells:

* Compatible family member or an unrelated donor (allogenic transplant)

* An identical twin (syngeneic transplant)

Patient's own cells previously collected and suitably stored (autologous transplant)