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3362 Clinical Outcomes in Fresh Versus Cryopreserved Hematopoietic Stem Cell Products in British Columbia: A Retrospective Study

Program: Oral and Poster Abstracts
Session: 711. Cell Collection and Processing: Poster II
Hematology Disease Topics & Pathways:
Research, ALL, Biological therapies, Lymphoid Leukemias, AML, Acute Myeloid Malignancies, adult, Lymphomas, APL, elderly, Clinical Research, Diseases, clinical procedures, real-world evidence, Therapies, aggressive lymphoma, Lymphoid Malignancies, young adult , Myeloid Malignancies, survivorship, Technology and Procedures, Study Population, Human, Transplantation
Sunday, December 11, 2022, 6:00 PM-8:00 PM

Bo Wan, MD1*, Lorenzo Lindo, BSc2,3, Giovanna Cameron3,4*, Yasser Abou Mourad, MD3,5*, Shanee Chung, MBChB, FRACP, FRCPA3,6, Donna L. Forrest, MD, FRCPC1,5, Florian Kuchenbauer, MD PhD1,7, Stephen H. Nantel, MD, FRCPC1,7, Sujaatha Narayanan, MBBS, MRCP, MRCPath1,7*, Thomas J. Nevill, MD, FRCPC1,7, Maryse Power, MB, FRCPI, FRCPath1,7, Judith A Rodrigo, MD, FRCPC1,7*, David Sanford, MD1,7, Kevin Song, MD, FRCPC3,5, Ryan J Stubbins, MD, MSc3,5, Heather J. Sutherland, MD, PhD, FRCPC1,7, Cynthia L. Toze, MD, FRCPC, MSc1,7*, Jennifer K. White, MD3,5*, Claudie Roy, MD, FRCPC1,7* and Kevin A. Hay, MD, MSc, FRCPC3,4,5,8

1Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
2Terry Fox Laboratory, British Columbia Cancer Research Institute, Vancouver, BC, Canada
3Faculty of Medicine, University of British Columbia, Vancouver, Canada
4Clinical Cell Therapy Laboratory, British Columbia Cancer Agency, Vancouver, Canada
5The Leukemia/Bone Marrow Transplant Program of BC, British Columbia Cancer Agency, Vancouver, Canada
6The Leukemia/Bone Marrow Transplant Program of BC, British Columba Cancer Agency, Vancouver, Canada
7The Leukemia/Bone Marrow Transplant Program of British Columbia, British Columbia Cancer Agency, Vancouver, BC, Canada
8Terry Fox Laboratory, British Columbia Cancer Research Centre, Vancouver, Canada


Allogeneic hematopoietic stem cell transplant (alloHSCT) is a mainstay of treatment for hematologic malignancies such as acute leukemias and aggressive lymphomas. Conventionally, fresh donor hematopoietic progenitor cells (HPC) are used, but the COVID-19 pandemic forced many centres to switch to cryopreservation of HPC for alloHSCT. We aimed to compare the outcomes in alloHSCT patients who received cryo-HPC with a recent historical cohort of patients who received fresh-HPC at our centre.


A retrospective chart review was conducted on all adult patients who received a bone marrow (BM) or peripheral blood alloHSCT in British Columbia between June 2017 and Jan 2022; cryo-HPCs were the predominant product used as of March 2020. CIBMTR criteria were used to define engraftment. Patients who died before 30 days post-alloHSCT were excluded from primary graft failure (GF) and GVHD analysis; those who died before 100 days post-alloHSCT or had primary GF were excluded from secondary GF and chronic GVHD analysis. Patients who were alive on the date of last follow-up (January 31, 2022) were censored. Statistical significance was calculated using the Chi square test for categorical variables and T-test or Mann-Whitney U test for continuous variables. Kaplan-Meier curves were plotted for OS.


A total of 271 alloHSCT procedures were included in the analysis, of which 134 received fresh-HPC and 137 cryo-HPC. The median age at the time of transplant was 54 years [IQR 46-64] in the fresh-HPC vs 59 [IQR 39-61] in the cryo-HPC group (p=0.02). Male recipients comprised 60% of both groups (p=1). There was no significant difference in primary diagnosis (p=0.17); AML was the most frequent indication (46% fresh-HPC vs 35% cryo-HPC), followed by ALL/LBL (20% vs 23%). Most patients were in CR1 (63% vs 53%, p=0.01).

The median CD34+ cell count infused was 7x106/kg in the fresh and 6x106/kg in the cryo-HPC group (p=0.08). For the cryo-HPC, the median time from cell collection to cryopreservation was 33 hours [IQR 23, 55], with a median cell viability of 96% [IQR 95, 98].

Matched unrelated donor was the most common donor type, which comprised 75% alloHSCTs in the fresh-HPC and 54% in the cryo-HPC group (p<0.01). Bone marrow source was used for 8% and 5% of alloHSCTs in the fresh-HPC and cryo-HPC groups, respectively (p=0.10). Myeloablative condition was used in 78% fresh-HPC vs 72% cryo-HPC (p=0.31) and busulfan/fludarabine was the most common regimen (47% vs 58%, p=0.01). Most patients received GVHD prophylaxis with cyclosporine and methotrexate ± Thymoglobulin (96% in fresh HPC, 79% in cryo-HPC, p<0.01)

The median follow-up was 16 months in fresh [IQR 10, 25] vs 10 months in the cryo-HPC group [IQR 5, 15] (p<0.01). Median overall survival (OS) was not reached in either group, and the 10-month OS was similar in both groups (79% fresh-HPC vs 78% cryo-HPC, p=0.74). There was no difference in OS between the groups in the patients with a diagnosis of acute leukemia (p=0.57).

Relapse rates were similar (27% fresh-HPC vs 23% cryo-HPC, p=0.60) with a median time to relapse of 5 months [IQR 3, 12] vs 3 months [IQR 3, 7] respectively (p=0.07). 10-month non-relapse mortality was 16% in fresh-HPC vs 13% in the cryo-HPC group (Fig 1b, p=0.47). There were no significant differences in causes of death; disease relapse was the most common cause of death (51% fresh-HPC, 56% cryo-HPC).

Median neutrophil engraftment was faster in patients receiving fresh-HPC at 18 days [IQR 15, 22] vs 20 [IQR 17, 23] with cryo-HPC (p<0.01). Median platelet engraftment was also faster for fresh-HPC with 19 days [IQR 16, 23] compared with 22 [IQR 18, 29] with cryo-HPC (p<0.01). There was 1 case of primary GF in the fresh-HPC compared to 5 in the cryo-HPC groups (p=0.07), and 4 cases of secondary GF when using fresh-HPC compared to 3 with cryo-HPC (p=0.46).

The incidence of grade II-IV acute GVHD was 30% in fresh HPC and 23% in cryo-HPC (p=0.06). The preliminary incidence of chronic GVHD was 43% in fresh HPC vs 33% in cryo-HPC (p=0.01).

Cryo-HPC may have prolonged time to neutrophil and platelet engraftment compared to fresh-HPC as well as increased incidence of primary graft failure. There were no significant differences in OS, relapse or acute GVHD among patients receiving fresh vs cryo-HPC in our cohort. Chronic GVHD was more common with fresh-HPC, likely due to longer follow-up times. These findings are consistent with those reported in literature.

Disclosures: Chung: Takeda: Honoraria; Astellas: Honoraria. Nevill: Abbvie: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees; BMS: Membership on an entity's Board of Directors or advisory committees; Alexion: Membership on an entity's Board of Directors or advisory committees; Taiho: Membership on an entity's Board of Directors or advisory committees; Pfizer: Membership on an entity's Board of Directors or advisory committees. Sanford: Astellas: Other: Advisory Board ; Abbvie: Other: Advisory Board ; Pfizer: Research Funding. Song: Amgen: Honoraria; Takeda: Honoraria; Janssen: Honoraria; Celgene: Honoraria, Research Funding. Sutherland: Karyopharm: Research Funding; GSK: Research Funding; Janssen: Consultancy, Research Funding; Amgen: Consultancy; Celgene: Consultancy; Sanofi: Consultancy. Hay: Janssen: Research Funding; Kite/Gilead: Honoraria; BMS: Honoraria; Novartis: Honoraria; Jazz Pharmaceuticals: Honoraria.

*signifies non-member of ASH