DELAYED platelet engraftment (PE) post-autologous stem cell transplantation (ASCT) in patients with non-Hodgkin lymphoma (NHL) can lead to severe outcomes; mainly due to the increased risk of life-threatening bleeding. However, there are limited data on the predictors of delayed PE post-ASCT in patients with NHL, and a study presented at the EBMT 2024 Annual Meeting aimed to identify such predictors.
The study retrospectively analysed patients with NHL who underwent ASCT at a single centre between 2007–2022. PE was defined as the recovery of platelet count above 50×10⁹ /L for 3 consecutive days without transfusion support, with the first day marked as the day of platelet engraftment. Various factors influencing platelet engraftment were analysed using statistical methods such as the Gray test for univariate analysis and Fine-Gray methods for multivariate analysis.
Among the 146 patients included, most were male with a median age of 54 years (64.0%), 93.0% had B-lymphoma, and 8.0% had T or T/NK-lymphoma. Many presented with advanced disease stages (57.4%), extranodal involvement (64.0%), and bone marrow involvement (39.0%). Patients with ASCT underwent a median of one apheresis session, with platelet counts at D-7 averaging 168×10⁹ /L, and infused CD34+ cells at 2.76×10⁶ /kg. The median time for PE was 17 days, with a median of five platelet transfusion units. Notably, 18% of patients failed to achieve PE by Day 60 post-transplant, and 5% died without engraftment.
Univariate analysis revealed associations between PE time and factors such as the number of therapeutic lines before ASCT (p=0.020), apheresis sessions (p=0.005), pre-transplant platelet count (p=0.005), and previous radiotherapy (p=0.030). However, multivariate analysis identified that having ≥2 therapeutic lines prior to ASCT and a pre-ASCT platelet count >150×10⁹ /L were independently associated with prolonged PE time. For a median follow-up of 70.6 months, median progression-free survival was 109.5 months, and the median overall survival was not reached. Interestingly, time to PE did not correlate with progression-free survival (p=0.506) or overall survival (p=0.965). Additionally, a previously published score for predicting PE was not found to be associated with actual PE occurrence in this cohort.
The team concluded that the number of therapeutic lines before ASCT and low pre-transplant platelet count were significant predictors of delayed PE in patients with NHL undergoing ASCT.
