Optimizing peripheral blood stem cells transplantation outcome through amend relapse and graft failure: a review of current literature

Trends in utilization of stored cryopreserved autologous peripheral hematopoietic cells intended for a second (or beyond) autologous hematopoietic cell transplantation in patients with multiple myeloma: a single center experience

Due to the advent of effective novel therapies for multiple myeloma (MM), the use of cryopreserved autologous peripheral blood hematopoietic cells (APBHC) for a salvage autologous transplant (auto-HCT) is in decline. We evaluated utilization trends and costs associated with cryopreserved APBHC in patients with MM. We retrospectively evaluated the clinicopathologic data from 440 patients with MM who underwent APBHC mobilization and collection at Mayo Clinic Florida between 2010 and 2019. Based on institution-specific charges as of May 2021, the cost of 1 session of APBHC collection/apheresis was $4,680 and the cost of 1 year of APBHC cryopreservation was $4,790 per patient. Out of 347 patients who had APBHC in cryopreservation, 5 (1.4%) underwent a salvage auto-HCT and 61% of patients had ≥1 excess collection sessions for APBHC that ultimately went unused. The median cost of excess collection sessions was $4,680 per patient (range, $4,680-$32,760) and the median total cost for excess collection sessions plus costs for storage was $23,840 per patient (range, $4,680-$85,450). The sum of costs of excess collection sessions was $2,077,920 and the sum of costs of cryopreservation was $5,812,665. Institutional policies regarding universal APBHC collection and long-term storage should be reevaluated in the era of novel therapeutics.

Use of Backup Stem Cells for Stem Cell Boost and Second Transplant in Patients with Multiple Myeloma Undergoing Autologous Stem Cell Transplantation

Autologous hematopoietic stem cell transplantation (ASCT) is a standard treatment for multiple myeloma (MM). Consensus guidelines recommend collecting sufficient stem cells in case there is a need for stem cell boost for delayed/poor engraftment or for future second ASCT. However, collecting and storing backup stem cells in all patients requires significant resources and cost, and the rates of backup stem cell utilization are not well studied. We sought to examine the utilization of backup stem cells (BSCs) in patients with MM undergoing ASCT. Patients with MM aged ≥18 years old who underwent first ASCT at our institution from January 2010 through December 2015 and collected sufficient stem cells for at least 2 transplants were included in this single-center retrospective study. This timeframe was selected to allow for adequate follow-up. A total of 393 patients were included. The median age was 58 years (range, 25-73). After a median follow-up of 6 years, the median progression-free survival (PFS) of the cohort was 3 years. Sixty-one percent (n = 240) of patients progressed or relapsed. Chemotherapy-based mobilization was used in almost all patients (98%). The median total CD34+ cells collected was 18.2 × 106/kg (range, 3.4-112.4). A median of 5.7 × 106 CD34+ cells/kg (range, 1.8-41.9) was infused during the first ASCT, and a median of 10.1 × 106 CD34+ cells/kg (range, 1.5-104.5) was cryopreserved for future use. Of the patients, 6.9% (n = 27) used backup stem cells, with 2.3% (n = 10) using them for stem cell boost, 4.6% (n = 18) for a second salvage ASCT, including 1 patient for both stem cell boost and second ASCT. Rates of backup stem cell use among patients aged <60, 60-69, and ≥70 years were 7.8%, 5.7%, and 5.9%, respectively. There was a trend toward higher rates of backup stem cell use for second ASCT in patients who were younger, had suboptimal disease control at time of first ASCT, and longer PFS. The median dose of stem cell boost given was 5.6 × 106 CD34+ cells/kg (range, 1.9-20). The median time from stem cell boost to neutrophil, hemoglobin, and platelet engraftment was 4 (range, 2-11), 15 (range, 4-34), and 12 (range, 0-34) days, respectively. Lower CD34+ dose and older age at time of ASCT predicted need for stem cell boost. With new salvage therapies for relapsed MM, the rates of second ASCT are very low. The low rates of use suggest that institutional policies regarding universal BSC collection and long-term storage should be reassessed and individualized. However, need for stem cell boost in 2.3% of patients may present a challenge to that.

An alternative test for determining autologous stem cell transplantation cell harvesting outcome: Comparison between predictive values of two tests

Daily CD34+ cells enumeration as a success indicator of stem cell pheresis procedure using flow cytometry is costly, lengthy, and labor-intensive. Thus, finding a simpler method to achieve the optimum time for harvesting the minimum required stem cells for transplantation could be helpful. The aim of this study was to evaluate the predictive value of reticulocytes fractions and their sensesivity and specificity in guiding CD34+ cell harvesting by G-CSF mobilization strategy. In this study, 49 candidates for autologous peripheral blood stem cell transplantation were enrolled. Before leukapheresis, the immature reticulocytes fraction (IRF) and CD34+ cell count were measured. Moreover, patients were evaluated for leukapheresis outcomes in two MNC and cMNC groups. Here we demonstrated that IRF, LFR, and MFR with the associated criterion of >17.3, ≤82.5, and >15.9, respectively, earned 100 % specificity and 47.2 %, 47.22 %, and 41.46 % sensitivity to predict the minimum required CD34+ cell count. Furthermore, IRF-V (Value) and MFR-V with the associated criterion of >0.77 and >0.55, respectively, earned 58.33 %, 66.67 % sensitivity and 84.62 %, 69.23 % of specificity, separately. As only MFR-V was able to predict the platelet engraftment (P-value = 0.014), none of the other above mentioned factors were not able to predict the neutrophil engraftment. Likewise, it was shown that patients who underwent MNC leukapheresis had a statistically significantly higher total WBC, harvested CD34⁺ cells, MNCs/ kg, and lower apheresis durations (P-values<0.05). Taken together, using IRF and its maturity stages seems to be a compelling predictor of minimal required CD34+ cells in autologous peripheral blood stem cell transplantation.

Photopheresis of a less than 10-kg child with acute graft versus host disease accompanied with hyperbilirubinemia: A case report

Hematopoietic stem cell transplantation is a curative treatment for many hematologic malignancies with its most important side effect being graft-versus-host disease (GVHD). Herein, we present a 3.5 year-old male with weight of 9.8 kg with acute GVHD (grade IV gastrointestinal and cutaneous) who did not respond to the first line therapies (corticosteroids). Thus, the patient was a candidate for extracorporeal photochemotherapy (ECP). Due to the hyperbilirubinemia, two sessions of ECP every week as well as one session of plasmapheresis 24 h before each ECP session were performed (Spectra^™Optia^® apheresis system). The procedures were performed successfully without any side effects and the GVHD manifestations of skin and GI responded perfectly to the treatment after 12 and 14 sessions of ECP, respectively. According to the results, it seems that ECP could be successfully performed in even less than 10-kg patients.

The effects of lower CD34 yields after lowe dose G-CSF induction on long-term autologous stem cell transplantation outcome: A single center study

Peripheral blood stem cell transplantation (PBSCT) is an effective treatment for hematological malignancies. Mobilization of peripheral blood stem cells performs in different ways among transplantation centers. Since the Effects of lower CD34+ cells dose after low dose G-CSF induction on autologous stem cell transplantation outcomes are not studied much, so this study was performed for this purpose. 735 autologous stem cell transplanted patients with diagnoses of multiple myeloma (n = 330), Hodgkin lymphoma (n = 200), non-Hodgkin lymphoma (n = 129), acute myeloid leukemia (n = 54) and solid tumors (n = 22) were retrospectively evaluated. G-CSF was administered at the dose of 5 μg/kg/day during mobilization and all patients except acute myeloid leukemia received 10 μg/kg/day on the last day. Peripheral blood stem cells were harvested in one session for all patients. The amount of injected CD34+ cells/kg for patients were divided and studied in four groups: <0.5 × 10⁶ (n = 36), 0.5-1.0 × 10⁶, (n = 132), 1.0-2.0 × 10⁶ (n = 226) and >2.0 × 10⁶ (n = 305). The median time of follow up was 26.9 months. The amount of CD34+ cells dose were a significant predictor of platelet engraftment, but overall survival, relapse-free survival and also relapse rate was not associated with cells yield. More platelet transfusion (P = 0.003) and antibiotics prescription (P = 0.001) in transplanted patients with lower CD34 cells dose should be balanced with risks of higher G-CSF doses administration and also its side effects. Our results declare that lower CD34 yields after lowe dose G-CSF induction are probably not a troublesome issue affecting transplantation outcomes.