Bone Marrow Transplantation: A Lifesaving Treatment for Leukemia and Lymphoma

Blood, though not an organ but an essential component which sustains life of brain, heart and other vital parts of the body. From transporting nutrients in vital organs to maintaining temperature of the body, the blood components play a significant role in immune response, blood clotting and tissue repair mechanism.

Considering the significant role it plays in proper functioning of the body, it’s not hard to imagine what happens if the blood is compromised. One of the most common conditions being blood cancer, among which is leukaemia and lymphoma, the two deadliest forms of blood cancers. 

Understanding Bone Marrow

Often regarded as a factory of blood cells, Bone marrow is a soft tissue found in long bones, including the spine, hips, ribs, sternum, and pelvis.

Bone marrow, though, consists of various tissues; the most significant part is stem cells present there. These cells divide and form RBCs, WBCs, and platelets by a process known as haematopoiesis.

Almost 220 billion new blood cells are formed by bone marrow every day and released into the bloodstream via small capillaries whenever required. 

This suggests that when these stem cells are functioning optimally, they regulate the immune system, facilitate tissue repair, and contribute to overall health.

However, sometimes, blood complications may occur, affecting the ability of the body to function properly.

Complications of Bone Marrow- Leukaemia and Lymphoma

Since bone marrow plays a major role in the blood formation, most of the blood complications can be attributed to changes in bone marrow. 

These changes are called mutation, which may lead to cancer (uncontrolled growth of blood cells). 

With a global incidence of 1.24 million cases each year, blood cancer has become prevalent worldwide. 

In the realm of blood disorders, leukaemia and lymphoma stand out as two of the most prevalent and critical hematologic cancers.

Leukaemia arises in the bone marrow and leads to abnormal, uncontrolled growth of white blood cells (WBC), known as leukocytes. The main role of WBCs is to protect the body from infection and any other foreign antigens like bacteria and viruses.

If the person is suffering from leukaemia, the bone marrow begins to produce an excessive number of abnormal white blood cells that do not function properly. As a result, people with leukaemia often experience a weakened immune system, making them more susceptible to infections. 

Based on the type of leukocyte affected, leukaemia can be of two types:

Lymphocytic Leukaemia: This affects lymphocytes, a type of WBC which plays a key role in immune response. 

Myeloid Leukaemia: This form of leukaemia targets the myeloid cells, which develop into red blood cells, white blood cells (except lymphocytes), and platelets. 

Both these types of leukaemia may be acute (fast- growing) and chronic (takes years to show symptoms). Without proper treatment, this condition may result in a cascade of life-threatening health issues. 

Another form of cancer is lymphoma, which begins in lymphocytes. These lymphocytes are normally found in lymph nodes, spleen, bone marrow, and other parts of the lymphatic system and play a central role in preventing infections.

Lymphoma is a malignant form of tumour where lymphocytes grow and multiply uncontrollably. These abnormal cells can build up in the lymph nodes and other parts of the lymphatic system, causing them to become swollen.

The two major types of lymphomas include:

Hodgkin lymphoma

This condition is characterised by the presence of Reed-Sternberg cells, a giant, typically multinucleated abnormal lymphocyte. Often diagnosed during biopsies, they usually affect young adults and adolescents. This type of lymphoma is easy to treat as it spreads in an orderly manner from one lymph node group to another, making it easier to detect and treat in its early stages.

Non-Hodgkin lymphoma

It is a more diverse group of lymphomas that are devoid of Reed-Sternberg cells. Most commonly seen in older adults, but it can affect people of all ages. Since, the spread of non-Hodgkin lymphoma is less predictable, hence treatment outcomes depend on the specific type of lymphoma.

Any deviation from normal behaviour of immune cells impacts the way our immune system deals with the antigen, hence it must be addressed timely.

Bone Marrow Transplant- A Treatment Approach for Leukaemia and Lymphoma

Both lymphoma and leukaemia are blood cancers that affect WBCs and, thus, the immune system.

Some of the common treatment methods include therapies such as radiation therapy, chemotherapy, immunotherapy, etc.

In some patients, the high doses of radiation in the therapies may severely damage the bone marrow, preventing it from producing healthy blood cells. Sometimes, cancer doesn’t respond well to the therapeutic approach or is considered high-risk. 

Bone marrow transplant (BMT) can be a lifesaver in these circumstances.

Also known as stem cell transplant, BMT is done to optimise the number of healthy bone marrow where the patient’s bone marrow has to be replaced with healthy bone marrow from the donor. The types of BMT are-

Autologous BMT 

After the therapy, there is a high probability that healthy bone marrow get destroyed along with tumours In autologous BMT, stem cells are taken from the patient’s own body before they are introduced with the high-dose chemotherapy or radiation treatment.. After this, the stem cells are transplanted into the patient’s body, which is healthy and capable of producing healthy blood cells.

Autologous BMT is usually a preferred method for leukaemia treatment.

Allogeneic BMT

In Allogeneic BMT, the source of stem cells to be transplanted is another healthy person (donor). Most of the time, parents, children, and other relatives are found to be good matches. There are two categories of donors within this BMT:

• Related donor

In this, the stem cell donor is genetically related to the patient, who could be a sibling as they have more than 50% chance of being a half HLA match. Sometimes, parents and children can also be donors, however the chance of being a complete match is lower in such cases.

• MUD (Matched Unrelated Donor)

MUD refers to a donor who is not blood-related to the recipient but shares a close genetic match, specifically in terms of human leukocyte antigens (HLAs).

These antigens are proteins found on the surface of cells that help the immune system identify and recognise foreign substances.

A close genetic match in HLAs is crucial for successful bone marrow transplants.

Bone Marrow Transplant: A Life Saviour for Leukaemia and Lymphoma Patients

Some leukaemia and lymphoma patients don’t respond well to the treatment approach due to the advanced and progressive stage of cancer. Hence, to save their lives, a bone marrow transplant (BMT) is done. Other medical conditions where BMT is often the treatment of choice for leukaemia and lymphoma include:

High Risk of Relapse

• Even after completing initial treatments and therapy cycles, if cancer cells are detected via blood tests and bone marrow biopsies in the body, it indicates a higher risk of relapse.
• Some genetic mutations can increase the chances of relapse even after the treatment. In chronic myeloid leukaemia (CML), the Philadelphia chromosome is a genetic abnormality that can contribute to a higher relapse risk. When the doctor diagnoses CML, they refer to genetic testing for the Philadelphia chromosome or Bcr-Abl so that they can create a treatment plan with minimal chances of relapse.

No Other Effective Treatment Options

Sometimes, the cancer cells may develop resistance to chemotherapy, radiation therapy, or targeted therapies, making these treatments less effective.

If the cancer has relapsed several times despite different treatment approaches, it may indicate that the cancer is becoming difficult to treat.

Bone Marrow Transplant: Challenges and Side effects

While BMT can be a life-saving procedure, it’s important to note that it’s not without its challenges. The process involves risks, and the success of the transplant depends on various factors, including the patient’s overall health and the donor match.

One of the most significant challenges is finding a compatible donor. Not everyone gets a suitable match within their family. This necessitates searching for a donor with the best possible HLA match. This can be a stressful and time-consuming process for patients and their families.

Nonetheless, it is not even without its risks, some of which include:

• Graft-versus-host disease (GVHD): This is a serious complication where the donated bone marrow cells are recognised as a foreign body. It can cause a range of symptoms, from skin rashes to organ damage.
• Infections: Since the body’s immune system is compromised after a transplant, patients are more susceptible to infections. These can lead to bacterial, viral and other forms of pathogenic infection.
• Bleeding: The transplant process can affect blood clotting, leading to an increased risk of bleeding.
• Organ damage: The transplant procedure itself can sometimes damage organs like the liver or lungs.
• Rejection: The body may reject the donated bone marrow cells, leading to a failed transplant.
• Psychological stress: The transplant process can be emotionally taxing for both the patient and their family.

It’s important to discuss these risks with the best bone marrow transplant doctors in India before deciding to undergo a bone marrow transplant. They can provide more specific information about the risks and benefits based on your individual circumstances.

Conclusion

Advances in medical science, particularly in Bone Marrow Transplantation (BMT), have offered new hope for patients with leukaemia and lymphoma. While BMT comes with challenges and risks, its potential to restore healthy blood cell production and save lives makes it a valuable option for many.

The decision to undergo a BMT is a significant one. With the right medical guidance and personalised care from the best cancer hospitals in India, however, it can be the beginning of a renewed, healthier life for those battling life-threatening blood cancers.