Several studies have been conducted to compare bone marrow and cord blood transplants. Both are found to exhibit pros and cons. Cord blood’s true potential has not yet been discovered fully. However, discussions have been there concerning its immunological adaptability and naivety. This knowledge gap combined with other crucial factors necessitates more clinical and scientific research. This is to understand cord blood’s efficacy to treat diverse disorders. But there are some issues faced like having a tough time to identify a matching donor. Also are faced greater re\lapse chances, graft failure and high mortality related to bone marrow transplants. It also involves high cost.
Studies conducted have revealed the benefits derived from cord blood transplant when compared to bone marrow in non-cancerous and cancerous disorders.
Cord blood in stem cell transplants outperforms bone marrow
If the cancer patient is recommended a transplant, then four common donor sources are identified. It includes from donor database (matched unrelated donor), sibling (matched related donor), umbilical cord blood and half-matched donor. Each approach is known to constitute its own pros and cons. However, a matched sibling is considered to be the primary choice followed by matched unrelated donor. Then follows cord blood with half-matched donors being the last option. Those not having initial two options are recommended the last two.
Researchers were said to have compared the results of double-unit cord blood and matched bone marrow transplants conducted in adults. The objective here was to identify which one among the two was the best stem cell source. Studies conducted over the comparison ran for about 7 years. Approximately 190 cord blood patients meant for transplantation were compared with 123 patients recommended for matched donor transplant.
The results showed that cancer patients who have undergone cord blood transplants were reported to show quick improvement. Moreover, they also experienced fewer complications when compared to those receiving matched sibling donor transplants.
Some key findings from this study are as follows:
- Much lower relapse rate in patients having received cord blood transplantation procedure.
- There were higher chances to develop graft vs. host disease with bone marrow unlike cord blood transplants.
- Treatment protocol also showed positive impact on the life quality of the patient.
- Lack of complications combined with improved overall recovery rate resulted in fewer expenses that are crucial in post-transplant care.
Researchers conclude that the study supports cord blood transplant efficacy. They also suggested that cancer patients provided with higher dosage of pre-transplant radiotherapy or chemotherapy should be recommended with cord blood as the preferred stem cell transplant source.
Core blood transplantation procedure outperforms matched bone marrow related donor transplants
Attempts were made to develop a low-risk, universal option to treat non-cancerous conditions like hunter syndrome, thalassemia, etc. A study conducted involved 44 children who were suffering from different types of immune and non-cancerous disorders along with chemotherapy in low dosage. There were given HLA-mismatched core blood of single unit without any cell expansion.
It was considered to be the very first largest trial and a unique study. It was conducted to demonstrate cord blood transplantation outperformed bone marrow concerning event-free survival, treatment related mortality and graft failure. Doctors and patients do get the confidence required to go ahead with the procedure especially in countries where finding matching donors can be a tough task.
The results showed the following:
- 1-year low TRM (Treatment-related Mortality) of 5%. It resulted in EFS (Event-free survival) of over 90% at one year.
- Less than 5% graft failure was noticed in this trial for non-manipulated cord blood grafts with regards to cancerous and non-cancerous diseases.
- The trial did not suggest any cell expansion. Sufficient stem cells are not present within a single unit of cord blood to treat adults.
- Single allogeneic cord blood unit is identified for each eligible child irrespective of their ethnicity. It demonstrated unparalleled and unique cord blood graft suitability without being HLA (perfect matching).
- The trial used this novel treatment protocol that promoted immune reconstitution and helped prevent graft failure.
- Patients did not develop any severe chronic graft or host disease. They rather experienced distinct improvement in their life quality.
The results demonstrated that expensive or complex cell-expansion techniques or extra supportive stem cell units will not be necessary like the double cord or haplo cord. A single non-expanded or mismatched cord blood is likely to perform better when compared to other available sources with regards to event-free survival, treatment-related mortality and transparent (graft) failure.
Challenges faced
Some major challenges are to be addressed despite positive findings. It includes:
- Insufficient stem cell\ number within a single cord blood unit.
- Difficulty in identifying a matching donor to enable stem cell transplant.
- High cost to store, retrieve and transplant cord blood stem cells.
You can discuss with your doctor and get to know more about cord blood and tissue transplantation.