Improving the donor experience
With the opening of Anthony Nolan’s Cell Collection Centre in September, we can now work towards more life-saving transplants happening on the best day for the patient.
But we also have a unique opportunity to improve our donors’ experience, by running more of our own donor-focused research to help improve stem cell transplants for both patients and donors.
A new project from our clinical research team, led by Dr Tania Dexter, is aiming to help reduce the number of times donors are asked to return for a second day of donation. This has the potential to get stem cell donations to patients faster, free up crucial donation slots at our cell collection centre, and potentially reduce the burden on donors.
The unpredictability of two-day donations
Around 30% of adults donating peripheral blood stem cells (PBSCs) to an unrelated patient need to return to their donation clinic for a second day, to ensure enough cells are collected for a successful transplant.
Because we can’t predict which patients will require two donation days, and which will only require one, we book two collection days for every PBSC donor. This means we have the best opportunity to collect enough cells for a patient; but also that significant number of bookings go unused.
It would be extremely useful for us to be able to predict which donors are most likely to only require a single day of donation – thereby cutting down on unnecessary two-day bookings for these donors and saving time for both our centre and our donors.
Predicting single day donations
Work by Dr Tania Dexter and Anthony Nolan’s clinical research team is beginning to unravel this problem. Analysing past data from donors between 2022 and 2024, the team found that several donor characteristics were associated with a higher chance of a single day donation. Scoring these characteristics together in a predictive model could help identify these donors.
The characteristics that mean a donor is more likely to donate in a single day are:
- Male
- Male donors tend to be more likely to donate enough cells in a single day – we’re not sure why yet, as this is independent of a donors’ weight, so it’s not just about male donors being on average larger and having more cells to donate.
- Over 80kg
- Donors who weigh over 80kg can produce more stem cells for us to collect, so they’ll be more likely to require only a single day of donation.
- Positive donor/recipient weight difference
- This factor was shown to be the most useful in predicting single day donations, so is effectively ‘counted twice’ by the predictive model. Patients with a lower weight require fewer cells for a successful transplant – so donors who weigh more than their matched patient are more likely to meet the cell requirement in a single sitting.
- Neutrophil count
- Neutrophils are the most common type of white blood cell, particularly helping the body fight bacterial infections. The more neutrophils a donor has, the more likely they are to require only a single day of donation – we’re still to discover why.
- Platelet count
- Platelets are tiny fragments of cells that help create blood clots. Donors with more platelets in their blood are more likely to require only a single day of donation, and similarly to the neutrophil count we don’t yet know why this is the case.
By combining these five characteristics into a scoring algorithm, the team could predict which donors were most likely to only require one day of donation. The algorithm scores out of six (because it counts donor/recipient weight difference twice) – donors who score 4/6 or more have a greater than 97% chance of donating in one day. The graph below shows the chances of a donor requiring only a single day of donation based on their score in the predictive model.
This model could now potentially be used to identify future donors with the highest chance of requiring only a single day of donation, with the aim of booking those donors in for a single day, thereby saving booking slots in our new cell collection centre.
It will be a while before this predictive model can be used in practice – we need to do more research to make sure it’s accurate and effective at our own collection centre.
This model represents the early stages of us utilising our new cell collection centre to conduct donor-centric research, with the aim of improving the donation experience and making the transplant process faster and more efficient for both patients and donors. I’m excited to see where this predictive model will lead us next.
Dr Tania Dexter, senior medical officer and lead researcher
What's next for research at the cell collection centre?
This newly developed predictive model has the potential to spearhead new research projects designed to improve the donation process.
Future research can look at interventions that could improve the number of donors who require a single day of donation. The predictive algorithm could help identify donors with a higher chance of needing a second donation day, and these donors could then be recruited to research projects that aim to help these donors produce enough cells in a single sitting.
Projects like these would not only help get donations to patients faster, and with more cells – but could save us time and money at the new cell collection centre, freeing up more slots for donations for both transplant and for medical research and treatments. This could also potentially reduce the burden on donors, by helping more donors require only a single day of donation.
Become a donor, potentially save a life
You could be the donor someone with a blood cancer or blood disorder is waiting for. Your stem cells could give a stranger a second chance at life. If you’re between 16-30, you can sign up to join the Anthony Nolan stem cell register here – it only takes a couple of minutes to complete our application form.