Bone Marrow Transplant vs Cord Blood Transplant - Which is Better?

Background of Transplants:

Historically, there have been numerous studies comparing cord blood and bone marrow transplants which have highlighted the pros and cons associated with both. Although there have been a few discussions claiming the naivety and immunological adaptability of cord blood, its true potential is not yet fully tapped. This gap in knowledge, as well as other key factors mentioned below, necessitate further scientific and clinical research to understand the efficacy of cord blood in the treatment of diverse disorders.

1. Difficulty in finding a matching donor.
2. High mortality, graft (transplant) failure and greater chances of relapse associated with bone marrow transplants.
3. High cost associated with a bone marrow transplant.

Recently ASH (American Society of Hematology) published 2 prospective studies in their journal Blood Advances which have clearly highlighted the benefits of a cord blood transplant over bone marrow and other sources in both cancerous and non-cancerous disorders.

Study 1

Cord blood outperforms bone marrow and other sources in stem cell transplants

Objective:

When a cancer patient is identified for a transplant, there are four common donor sources: matched related donor (sibling), matched unrelated donor (from a donor database), half-matched donor, or umbilical cord blood. Although there are pros and cons associated with each approach, the consensus has generally ranked a matched sibling as the first choice, followed by a matched unrelated donor, cord blood and finally half-matched donors. The last two options are reserved for patients without either of the first two options.

In order to identify the best source of stem cells, researchers from the University of Colorado compared the outcomes of matched bone marrow and double-unit cord blood transplants in adults. The comparison was studied over 7 years (2010-2017).  A total of 190 cord blood transplant patients were compared with 123 matched related donor transplant patients 

Results:

Outcomes of this study demonstrated that cancer patients undergoing cord blood transplants showed better improvement & developed lesser complications than those who received matched sibling donor transplants. The other key findings of the study are highlighted below:

1. Chances of developing graft versus host disease were higher with bone marrow as compared to cord blood transplants.
2. Relapse rates were lower in patients who received a cord blood transplant.
3. The overall improved recovery rate and lack of complications resulted in low costs associated with post-transplant care.
4. This treatment protocol had a distinct positive impact on the patients’ quality of life.

Take away message:

Authors of this study clearly support the efficacy of cord blood transplants and suggest that especially those cancer patients who receive high dose pre-transplant chemotherapy or radiotherapy, cord blood will be the preferred source for stem cell transplants.

Study 2

Cord Blood Transplants Outperform Matched Related Donor Transplants from Bone Marrow and Other Sources.

In an attempt to create a fairly universal & low-risk treatment option for non-cancerous conditions such as thalassemia, Hunter syndrome and so on, researchers from the University of Pittsburgh successfully treated 44 children suffering from various non-cancerous & immune disorders with a combination of low dose chemotherapy and single-unit of HLA-mismatched cord blood with no cell expansion. 

The successful outcomes provided by this first of its kind and the largest trial showed that cord blood outperformed bone marrow in terms of graft failure, treatment related mortality and event-free survival. Also, this gives tremendous confidence to patients & doctors in a multi-ethnic country like India where the chances of finding a matching donor are very low. 

Results:

1. The graft failure rate of <5% seen in this trial is the lowest ever reported for non-manipulated cord blood grafts in non-cancerous or even in cancerous diseases.
2. The lowest 1-year (Treatment-Related Mortality) TRM of 5%, resulting in >90% Event Free Survival (EFS) at 1 year was reported.
3. A single unit of allogeneic cord blood could be identified for each of the 44 eligible children regardless of their ethnicities, showing the unique and unparalleled suitability of cord blood grafts even without being perfectly (HLA) matched.
4. No cell expansion was required in the trial. In general, a single cord blood unit doesn't have sufficient stem cells to treat adults. 
5. No patient developed severe chronic graft versus host disease and a distinct improvement in the quality of life was reported.
6. The novel treatment protocol used in the trial prevented graft failure and aided immune reconstitution.

Take away message:

Outcomes of this largest study on non-cancerous blood disorders showed that there was no clinically pressing need for complex or expensive cell-expansion methodologies or additional supportive stem cell units such as double-cord (a combination of two cord blood units) or haplo-cord (a combination of cord blood unit and bone marrow form a half-matched donor). In fact, a single unit of mismatched and non-expanded cord blood performs better than other sources in terms of graft (transplant) failure, treatment-related mortality and event-free survival.

Current challenges:

In spite of all the positive findings reported by the studies above, there are still some major challenges that need to be addressed. These include: 

1. Difficulty in finding a matching donor for stem cell transplants. 
2. An insufficient number of stem cells in one cord blood unit.
3. In India, although there are only about 2000 cord blood transplants which take place each year, the current annual need for them stands at a staggering 50,000. In other words, only 4 % of people who require cord blood transplants are currently receiving them.
4. High cost associated with storage, retrieval & transplant of cord blood stem cells.

Why Is LifeCell Community Banking The Best Choice For Your Family?

1. LifeCell's Cord blood banking ensures infinite access to the world’s largest inventory of cord blood stem cells of Indian origin, giving every individual >97 % chance of finding a stem cell match.
2. Provides every customer access to an infinite number of matched stem cell units.
3. Offers a series of pocket-friendly stem cell storage plans & financial assistance up to Rs 20 lakh for every stem cell transplant.