Harvests from bone marrow donors who weigh less than their recipients are associated with a significantly increased probability of a suboptimal harvest yield

Abstract

BACKGROUND:Previous studies have demonstrated the importance of bone marrow (BM) harvest yield in determining transplant outcomes, but little is known regarding donor and procedure variables associated with achievement of an optimal yield. We hypothesized that donor demographics and variables relating to the procedure were likely to impact the yield (total nucleated cells [TNCs]/kg recipient weight) and quality (TNCs/mL) of the harvest. STUDY DESIGN AND METHODS:To test our hypothesis, BM harvests of 110 consecutive unrelated donors were evaluated. The relationship between donor or procedure characteristics and the BM harvest yield was examined. RESULTS:The relationship between donor and recipient weight significantly influenced the harvest yield; only 14% of BM harvests from donors who weighed less than their recipient achieved a TNC count of more than 4 3 10 8 /kg compared to 56% of harvests from donors heavier than their recipient (p 5 0.001). Higher-volume harvests were significantly less likely to achieve an optimal yield than lower-volume harvests (32% vs. 78%; p 5 0.007), and higher-volume harvests contained significantly fewer TNCs/mL, indicating peripheral blood contamination. BM harvest quality also varied significantly between collection centers adding to recent concerns regarding maintenance of BM harvest expertise within the transplant community. CONCLUSION:Since the relationship between donor and recipient weight has a critical influence yield, we recommend prioritizing this secondary donor characteristic when selecting from multiple well-matched donors. Given the declining number of requests for BM harvests, it is crucial that systems are developed to train operators and ensure expertise in this procedure is retained.T he past two decades have seen a reduction in the number of unrelated donor (UD) bone marrow (BM) harvests performed, as the proportion of transplants using peripheral blood stem cells (PBSCs) has increased. Although several studies have examined the clinical impact of BM composition on the outcome of hematopoietic stem cell transplantation, relatively few studies have concentrated on the donor or procedure characteristics that influence the yield from BM harvests. To achieve a concentrated high-quality harvest, minimization of peripheral blood contamination is essential. Several early studies demonstrated the benefit of small-volume aspirations (<5 mL) from multiple punctures sites as opposed to larger-volume aspirations.13-15 Stimulation of the BM by prior granulocyte-colony-stimulating factor administration can also improve the TNC yield per donor weight, 16 but this is not routine practice in UDs, where donor safety considerations are paramount. A study of 166 BM donors reported that both a higher donor body mass index (BMI) and donor weight were associated with an improved CD34 yield at BM harvest, while donor age, sex, and height had no impact on yield. 17Other studies have noted a correlation between high donor weight and increased quality (TNCs/mL) of BM harvested. 18,19 It is...

Bone marrow harvest in donors with anaemia

“…Anthias et al . showed that target TNC doses <4 × 10 8 /kg of recipient weight were achieved in 47% of harvests and 4·5% donors obtained an inadequate TNC yield (<2 × 10 8 /kg). Pruszczyk et al .…”

“…TNC doses of <3 × 10 8 /kg are associated with increased transplant mortality and inferior long‐term graft function and thus are considered suboptimal. Inadequate TNC dose is defined as <2 × 10 8 /kg . Anthias et al .…”

“…Taking into account, preharvest haemoglobin concentration could help to optimize harvested BM volume, minimizing the amount of adverse effects, for example, clinically significant anaemia, and limiting the number of suboptimal BMHs. However, impact of higher volume harvests on general outcome of BM transplantation is a subject of controversy and appropriate volume of BM harvested is still unknown . Some authors suggest that higher BM portions harvested were more likely to achieve fewer TNC/ml dose and, consequently, did not significantly improve engraftment and haematopoietic recovery .…”

“…Our research suggests that BMH is safe in donors with anaemia prior to procedure, although limited sample size may weaken its external validity. However, it might be impossible to obtain bigger groups even in multicentre studies as many centres will disqualify the donors with anaemia, and even the registry studies are often done on smaller donor populations .…”

Marrow harvesting: practice makes perfect

“…The study by Anthias and colleagues evaluated the characteristics influencing the quality of marrow harvests from donors of the Anthony Nolan Registry in the United Kingdom. Their findings suggest that, when available, donors of similar or higher weight to that of the recipient should be selected, as this would result in a significantly higher total nucleated cell dose.…”