Autologous hematopoietic cell transplantation: an update for clinicians

Epidemiology of early infections and predictors of mortality after autologous hematopoietic stem-cell transplantation among multiple myeloma, Hodgkin, and non-Hodgkin lymphoma: the first experience from Palestine

Background

Autologous hematopoietic stem-cell transplantation (HSCT) is the standard of care in many relapsed and refractory lymphoid malignancy, neuroblastoma, and multiple myeloma (MM). This study was conducted to describe the epidemiology of early infections that occurred within the first 100 days among patients who received HSCT for MM, Hodgkin (HL), and non-Hodgkin lymphoma (NHL) in Palestine.

Methods

This study was conducted in a retrospective cohort design in the only autologous HSCT in Palestine in the period between 2014 and 2021. The medical records of the patients were reviewed to identify and collect demographic, clinical, and microbiological data on bacterial, viral, fungal, and parasitic infections as diagnosed by cultures, polymerase chain reaction, and fluorescent antibody testing.

Results

A total of 145 patients were included in this study (median age = 44.0 [28.0, 53.5] years). Of those, 8 (5.5%) were younger than 18 years, 69 (47.6%) had MM, 53 (36.6%) had HL, and 23 (15.9%) had NHL. The source of fever had no focus in the majority of the cases 82 (56.6%), 12 (8.3%) had bloodstream infections, 8 (5.5%) had colitis, and 7.6 (5.0%) had pneumonia. Patients from whom gram-negative bacteria were isolated stayed in the hospital for longer duration compared to the other patients (median = 21.0 [19.0, 25.0] vs. 18.0 [15.0, 22.0] days, p-value = 0.043, respectively). The cumulative incidence of death in the first 100 days after infusion of stem cells was 3.4%. The cumulative incidence of death in the first 100 days post-transplantation was higher for patients with NHL compared to those with HL and MM (p-value = 0.017). Gram-negative and fungal infections were strong predictors of mortality.

Conclusion

Bacterial gram-positive and gram-negative infections were the most common early infections among patients who underwent autologous HSCT for hematological malignancies (HM) in the only center in Palestine. The findings of this study are informative to healthcare providers and planners of care for patients who are scheduled to receive autologous HSCT for HM.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-022-07709-4.

Selection of the mobilization regimen in lymphoma patients: A retrospective cohort study

BACKGROUND AND OBJECTIVES

Consolidation with autologous stem cell transplantation (ASCT) is recommended for patients with recurrent or refractory lymphoma after salvage chemotherapy. Stem cells which will be used in ASCT are provided by mobilization using granulocyte colony stimulation factor (G-CSF) or chemotherapy plus G-CSF. The aim of this study was to compare the effect of various mobilization regimens on the clinical parameters of lymphoma patients.

MATERIALS AND METHODS

Mobilization interventions of lymphoma patients were analysed retrospectively. The patients were divided into 3 groups according to the mobilization method implemented to collect stem cells before ASCT, (Group 1: Salvage chemotherapy plus G-CSF, Group 2: Cyclophosphamide plus G-CSF, Group 3: G-CSF alone).

RESULTS

Analysis of CD34⁺ cell counts of the 3 groups revealed a significant difference (p < 0.001). Although the number of CD34⁺ cells collected were different, the neutrophil and platelet engraftment of the 3 groups were similar (p > 0.05). Furthermore, the results were similar in the separate analysis of NHL and HL patients. While the mobilization success rate in group 1 was 97.8 %, it was 90.2 % in group 3. This difference showed a certain trend towards statistical significance (p = 0.074). Patients who received DHAP plus G-CSF had a higher CD34⁺ count, while neutrophil engraftment was shorter than with ESHAP plus G-CSF (p < 0.05).

CONCLUSION

Although the success rate of mobilization and number of CD34⁺ cell collected were higher in the salvage chemotherapy plus G-CSF than G-CSF alone, G-CSF alone group provided similar neutrophil and thrombocyte engraftment in most lymphoma patients.

Allogeneic transplantation in elderly patients ≥65 years with non-Hodgkin lymphoma: a time-trend analysis

Allogeneic hematopoietic cell transplantation (allo-HCT) is a curative therapy for relapsed/refractory and high-risk non-Hodgkin lymphoma (NHL). However, no large studies have evaluated allo-HCT utilization in elderly NHL patients (≥65 years). Using the CIBMTR registry, we report a time-trend analysis of 727 NHL patients (≥65 years) undergoing the first allo-HCT from 2000 to 2015 in the United States (US). Study cohorts were divided by time period: 2000-2005 (N = 76) vs. 2006-2010 (N = 238) vs. 2011-2015 (N = 413). Primary outcome was overall survival (OS). Secondary outcomes included progression-free survival (PFS), relapse/progression (R/P), and non-relapse mortality (NRM). Median age at transplant, use of reduced-intensity conditioning, and graft source remained stable, while use of unrelated donors increased in the most current era. The 1-year probabilities of NRM from 2000 to 2005 vs. 2006-2010 vs. 2011-2015 were 24% vs. 19% vs. 21%, respectively (p = 0.67). Four-year probability of R/P was similar among the three cohorts: 48% (2000-2005), 40% (2006-2010), and 40% (2011-2015) (p = 0.39). The 4-year probabilities of PFS and OS (2000-2005 vs. 2006-2010 vs. 2011-2015) showed significantly improved outcomes in more recent time periods: 17% vs. 31% vs. 30% (p = 0.02) and 21% vs. 42% vs. 44% (p < 0.001), respectively. Utilization of allo-HCT increased in elderly NHL patients in the US since 2000 with improving survival outcomes.

A retrospective study of autologous stem cell mobilization by G-CSF in combination with chemotherapy in patients with multiple myeloma and lymphoma

Factors affecting peripheral blood hematopoietic stem cell (PBSC) mobilization and collection were investigated in patients with multiple myeloma (MM) and lymphoma who were undergoing chemotherapy. Clinical data from 128 patients, including 53 MM and 75 malignant lymphoma (7 Hodgkin's lymphoma and 68 non-Hodgkin's lymphoma) cases were retrospectively analyzed. Autologous PBSCs were mobilized using granulocyte-colony stimulating factor (G-CSF) during chemotherapy, and collected using a continuous flow cell separation instrument. The yields of CD34+ cells per kilogram of patient body weight <2.0×10⁶/kg, >2.0×10⁶/kg or >5.0×10⁶/kg were defined as a failure, a success or ideal mobilization, respectively. In MM and lymphoma patients, the success rates of CD34+ cell acquisition were 73.6 (39/53) and 58.7% (44/75), the ideal rates were 43.4 (23/53) and 30.7% (23/75), and the failure rates were 26.4 (14/53) and 41.3% (31/75), respectively. Univariate and multivariate statistical analysis revealed that negative factors for PBSC mobilization in patients with MM were lenalidomide treatment, multiple chemotherapies, incomplete disease remission and low-level blood hemoglobin; in patients with lymphoma, the negative factors were the histological disease type, incomplete disease remission, being beyond the first-line of previous chemotherapy, multiple chemotherapies, chemotherapy with the HyperCVAD-B mobilization scheme, high-dose MTX/Ara-c (methotrexate/cytarabine) treatment, prolonged administration of G-CSF and low-hematocrit levels. In the present study, different factors influencing PBSC mobilization and collection in MM and lymphoma cases were identified. PBSC mobilization yielded sufficient CD34+ cell counts both in MM and lymphoma patients; however, the failure rates were relatively high.

Trends in peripheral stem/progenitor cell manipulation and clinical application

Transplants using peripheral blood hemopoietic stem/progenitor (PBHS) cells are widely performed for the treatment of patients with hematologic disorders in routine practice and clinical trials. Although the process from mobilization to infusion of PBHS cells has been mostly established, optimal conditions for each process remain undetermined. Adverse reactions caused by PBHS cell infusions have not been systematically recorded. In transplants using PBHS cells, a number of problems still exist. In this section, the current status of and future perspectives regarding PBHS cells are described.

Rationale for assessing the therapeutic potential of resveratrol in hematological malignancies

Promising results from pre-clinical studies on the naturally-occurring polyphenol resveratrol have generated considerable interest and somewhat excessive expectations regarding the therapeutic potential of this compound for treating or preventing various diseases, including cardiovascular and neurodegenerative disorders and cancer. Resveratrol has potent inhibitory activity in vitro against various tumor types, including cell lines derived from virtually all blood malignancies. Pharmacological studies have shown that resveratrol is safe for humans but has poor bioavailability, due to its extensive hepatic metabolism. Curiously, a substantial proportion of the orally administered resveratrol can reach the bone marrow compartment. Notably, various pathways dysregulated in blood cancers are known to be molecular targets of resveratrol, thus substantiating the potential utility of this agent in blood malignancies. In this review, we primarily focus on the scientific evidence that supports the potential utility of resveratrol for the management of select hematological malignancies. In addition, potential clinical trials with resveratrol are suggested.

Systemic therapy with oncolytic myxoma virus cures established residual multiple myeloma in mice

Multiple myeloma is an incurable malignancy of plasma B-cells. Traditional chemotherapeutic regimes often induce initial tumor regression; however, virtually all patients eventually succumb to relapse caused by either reintroduction of disease during autologous transplant or expansion of chemotherapy resistant minimal residual disease. It has been previously demonstrated that an oncolytic virus known as myxoma can completely prevent myeloma relapse caused by reintroduction of malignant cells during autologous transplant. The ability of this virus to treat established residual disease in vivo, however, remained unknown. Here we demonstrate that intravenous administration of myxoma virus into mice bearing disseminated myeloma results in the elimination of 70–90% of malignant cells within 24 hours. This rapid debulking was dependent on direct contact of myxoma virus with residual myeloma and did not occur through destruction of the hematopoietic bone marrow niche. Importantly, systemic myxoma therapy also induced potent antimyeloma CD8⁺ T cell responses which localized to the bone marrow and were capable of completely eradicating established myeloma in some animals. These results demonstrate that oncolytic myxoma virus is not only effective at preventing relapse caused by reinfusion of tumor cells during stem cell transplant, but is also potentially curative for patients bearing established minimal residual disease.

Hematopoietic Progenitor Cell Mobilization with Ifosfamide, Carboplatin, and Etoposide Chemotherapy versus Plerixafor-Based Strategies in Patients with Hodgkin and Non-Hodgkin Lymphoma

Studies comparing the efficacy and safety of chemo-mobilization with ifosfamide, carboplatin, and etoposide (ICE) ± rituximab with plerixafor-based approaches in lymphoma patients have not been performed. We analyzed hematopoietic progenitor cell mobilization outcomes in lymphoma patients undergoing chemo-mobilization with ICE (n = 35) compared with either routine plerixafor (n = 30) or "just in time" (JIT) plerixafor-based mobilization (n = 33). Chemo-mobilization provided a significantly higher total CD34(+) cell yield (median collection, 5.35 × 10(6) cells/kg for ICE versus 3.15 × 10(6) cells/kg for routine plerixafor and 3.6 × 10(6) cells/kg for JIT plerixafor, P < .001). The median day 1 yield of CD34(+) cells was not significantly different (median, 2.2 × 10(6) cells/kg in ICE versus 1.9 × 10(6) cells/kg in upfront plerixafor versus 1.7 × 10(6) cells/kg in JIT plerixafor, P = .20). There was no significant difference in the 3 groups in terms of total number of apheresis sessions performed (median, 2 in each group; P = .78). There were no mobilization failures (inability to collect at least 2 × 10(6) cells/kg) in the chemo-mobilization group, whereas 5 patients (16.7%) in the routine plerixafor and 3 patients (9.1%) in JIT group had mobilization failure (P = .04). Mean time to neutrophil engraftment was faster in the chemo-mobilization group, 10.3 days (±1.2) compared with 12.1 days (±3.6) in the routine plerixafor group and 11.6 days (±3.0) in the JIT group (P < .001) and mean time to platelet engraftment was 13.7 days (±.7) in ICE versus 20.3 days (±1.6) in routine plerixafor versus 17.1 days (± .9) in JIT group (P < .001). Red blood cell transfusions were significantly higher in the chemo-mobilization group (34.3% versus 0 versus 3.2% versus 1, P < .001) and so were the platelet transfusions (22.9% versus 0 versus 0, P < .001). Excluding the cost of chemotherapy administration, chemo-mobilization was associated with significantly less mobilization cost (average cost $17,601.76 in ICE versus $28,963.05 in routine and $25,679.81 in JIT, P < .001). Our data suggests that chemo-mobilization with ICE provides a higher total CD34(+) cell yield, lower rates of mobilization failure, faster engraftment, and lower cost compared to plerixafor-based approaches with comparable toxicity profile between the groups, except for higher transfusion requirements with chemo-mobilization.

Fluorine-19 Labeling of Stromal Vascular Fraction Cells for Clinical Imaging Applications

Stromal vascular fraction (SVF) cells are used clinically for various therapeutic targets. The location and persistence of engrafted SVF cells are important parameters for determining treatment failure versus success. We used the GID SVF-1 platform and a clinical protocol to harvest and label SVF cells with the fluorinated ((19)F) agent CS-1000 as part of a first-in-human phase I trial (clinicaltrials.gov identifier NCT02035085) to track SVF cells with magnetic resonance imaging during treatment of radiation-induced fibrosis in breast cancer patients. Flow cytometry revealed that SVF cells consisted of 25.0% ± 15.8% CD45+, 24.6% ± 12.5% CD34+, and 7.5% ± 3.3% CD31+ cells, with 2.1 ± 0.7 × 10⁵ cells per cubic centimeter of adipose tissue obtained. Fluorescent CS-1000 (CS-ATM DM Green) labeled 87.0% ± 13.5% of CD34+ progenitor cells compared with 47.8% ± 18.5% of hematopoietic CD45+ cells, with an average of 2.8 ± 2.0 × 10¹² ¹⁹F atoms per cell, determined using nuclear magnetic resonance spectroscopy. The vast majority (92.7% ± 5.0%) of CD31+ cells were also labeled, although most coexpressed CD34. Only 16% ± 22.3% of CD45-/CD31-/CD34- (triple-negative) cells were labeled with CS-ATM DM Green. After induction of cell death by either apoptosis or necrosis, >95% of ¹⁹F was released from the cells, indicating that fluorine retention can be used as a surrogate marker for cell survival. Labeled-SVF cells engrafted in a silicone breast phantom could be visualized with a clinical 3-Tesla magnetic resonance imaging scanner at a sensitivity of approximately 2 × 10⁶ cells at a depth of 5 mm. The current protocol can be used to image transplanted SVF cells at clinically relevant cell concentrations in patients.

SIGNIFICANCE

Stromal vascular fraction (SVF) cells harvested from adipose tissue offer great promise in regenerative medicine, but methods to track such cell therapies are needed to ensure correct administration and monitor survival. A clinical protocol was developed to harvest and label SVF cells with the fluorinated (¹⁹F) agent CS-1000, allowing cells to be tracked with (19)F magnetic resonance imaging (MRI). Flow cytometry evaluation revealed heterogeneous ¹⁹F uptake in SVF cells, confirming the need for careful characterization. The proposed protocol resulted in sufficient ¹⁹F uptake to allow imaging using a clinical MRI scanner with point-of-care processing.