Beyond body weight: investigating the impact of body surface area on graft CD34+ cell dosing: a single-center experience.

[BACKGROUND AIMS] This retrospective study investigated the impact of dosing CD34+ cells on the basis of body weight, body surface area (BSA) and body mass index (BMI) on neutrophil and platelet engraftment after autologous stem cell transplantation (SCT) in patients with multiple myeloma (MM).

[METHODS] We performed a retrospective chart review of 114 patients including 97 patients (48 male and 49 female) diagnosed with MM and 17 patients diagnosed with Non-Hodgkin lymphoma. The study categorized subjects on the basis of BMI (<25 and ≥25) and BSA (<1.9 m² and ≥1.9 m²).

[RESULTS] The findings revealed no significant difference in time to neutrophil engraftment after SCT for different BMI groups, which was on average 11.1 days. However, BSA played a significant role as patients with a BSA ≥1.9 m² exhibited delayed platelet engraftment in contrast to the low BSA group (18.55 days versus 16.42 days, P < 0.05). Furthermore, although CD34+ cell doses were comparable across groups when adjusted for body weight, a BSA-based analysis indicated a greater absolute number of CD34+ cells were administered to patients with BSA ≥1.9 m² (6.07 versus 4.78 cells × 10⁸/m², P < 0.05). By using a multivariate analysis, we showed that for neutrophil engraftment, the best predictive model included age, fat-free mass (FFM) and CD34+ cells (P < 0.1) along with BSA (P = 0.12). For platelet engraftment, the best predictive model included sex and FFM (P < 0.1), with BSA as a significant predictor (P = 0.02). Patients with greater BSA (≥1.9 m²) had a nonsignificantly shorter adjusted time to neutrophil engraftment (LS mean = 10.96) compared with those with lower BSA (<1.9) (LS mean = 11.23). However, greater BSA (≥1.9 m²) was significantly associated with a longer adjusted time to platelet engraftment (LS mean = 18.94) versus lower BSA (<1.9) (LS mean = 16.21).

[CONCLUSION] Our results highlight that male patients with a high BSA experienced a 4-day delay in platelet engraftment after autologous SCT. This delay emphasizes the need for optimized dosing strategies to enhance post-transplant recovery, particularly in patients with elevated BSA. Shortening the time to hematopoietic engraftment after SCT may significantly reduce hospital stays and lower the risk of infections, bleeding, and transfusion-related complications.