Predictive factors for poor mobilization in autologous stem cell transplant: a multivariate model

Inadequate stem cell mobilization remains a major challenge in autologous stem cell transplantation. Although multiple risk factors for poor mobilization have been suggested, their clinical utility is limited. This study aimed to identify predictors of poor mobilization and develop a clinically applicable predictive model.

A retrospective analysis of patients who underwent autologous stem cell transplantation was conducted. Poor mobilization was defined as a total CD34⁺ cell collection of less than 2 × 10⁶ cells/kg or the requirement for extended apheresis with multiple collection cycles.

A total of 430 patients with Hodgkin's lymphoma (n = 134), non-Hodgkin's lymphoma (n = 113), and multiple myeloma (n = 183) were included in this study. Poor mobilization was observed in 28.6% (123/430) of patients. A predictive model was developed using multivariate analysis, achieving an area under the receiver operating characteristic curve of 0.97 (p-value <0.001) when including the CD34⁺ cell count and 0.98 (p-value <0.001) when excluding it. Independent risk factors for poor mobilization included low platelet count, bone marrow infiltration, advanced disease status, and exposure to ≥2 alkylating agents. The final model demonstrated a specificity of 98.7% (95% CI: 96.7-99.6%) and a sensitivity of 91.1% (95% CI: 84.6-95.4%).

This predictive model can be applied before the initiation of the mobilization process. With sensitivity, specificity, positive predictive value, and positive likelihood ratio all exceeding 90% in both versions, the model demonstrates high effectiveness and clinical utility.