Identification of hematopoietic progenitor cell donor characteristics predicting successful mobilization: results of an Italian multicenter study.

BACKGROUND: Peripheral blood (PB) hematopoietic progenitor cells (HPC) collected by apheresis are the first-choice source for allogeneic stem cell transplantation. The target HPC dose is usually considered to be 4 × 10(6) CD34+ cells/kg of the recipient, but higher doses are required in reduced-intensity conditioning and haploidentical transplants. Thus, prolonged stimulation and repeated collections or failure to reach HPC target may occur, increasing risks for donors and recipients. We carried out a retrospective multicenter study on healthy donors, to identify donor variables which may correlate with HPC mobilization. STUDY DESIGN AND METHODS: HPC allogeneic donations from sibling and unrelated donors performed in two centers from 1995 to 2012 were analyzed. We defined a mobilization cutoff of 50 × 10(6) CD34+ cells/L and tested somatic variables, blood counts, and granulocyte-colony-stimulating factor (G-CSF) dose and molecular form. RESULTS: A total of 360 donors were analyzed (male, 201; female, 159; sibling, 348; unrelated, 12; median [range] age, 44.8 [13-80] years). Median peak CD34+ in PB was 54.4 × 10(6) /L (range, 5 × 10(6) -299 × 10(6) ). By multivariate analysis, we identified the following variables to correlate with good mobilization: 1) male sex (p<0.0005); 2) younger age (p=0.007); 3) higher baseline (premobilization) white blood cell (WBC) count (p<0.0005); 4) higher G-CSF dosage (p<0.0005); and 5) use of lenograstim rather than filgrastim (p<0.002). CONCLUSION: In healthy donors it is possible to predict successful HPC mobilization by donor sex, age, WBC count, and G-CSF form and dose. Furthermore, based on these data, it may be possible, at least in parental setting, to modulate G-CSF dosage on the basis of donor characteristics.

Adapting the Fitness Criteria for Non-Intensive Treatments in Older Patients with Acute Myeloid Leukemia to the Use of Venetoclax-Hypomethylating Agents Combination-Practical Considerations from the Real-Life Experience of the Hematologists of the Rete Ematologica Lombarda.

A retrospective survey was conducted in hematologic centres of the Rete Ematologica Lombarda (REL) on 529 older AML patients seen between 2020-2022. Compared to 2008-2016, the use of intensive chemotherapy (ICT) decreased from 40% to 18.1% and of hypomethylating agents (HMAs) from 19.5% to 13%, whereas the combination of Venetoclax/HMA, initially not available, increased from 0% to 36.7%. Objective treatment-specific fitness criteria proposed by SIE/SIES/GITMO in 2013 allow an appropriate choice between ICT and HMAs by balancing their efficacy and toxicity. Venetoclax/HMA, registered for patients unfit to ICT, has a unique toxicity profile because of prolonged granulocytopenia and increased infectious risk. Aiming at defining specific fitness criteria for the safe use of Venetoclax/HMA, a preliminary investigation was conducted among expert REL hematologists, asking for modifications of SIE/SIES/GITMO criteria they used to select candidates for Venetoclax/HMA. While opinions among experts varied, a general consensus emerged on restricting SIE/SIES/GITMO criteria for ICT-unfit patients to an age limit of 80-85, cardiac function > 40%, and absence of recurrent lung infections, bronchiectasis, or exacerbating COPD. Also, the presence of an adequate caregiver was considered mandatory. Such expert opinions may be clinically useful and may be considered when treatment-specific fitness criteria are updated to include Venetoclax/HMA.