Benefit of Granulocyte Colony-Stimulating Factor-Primed Donor Lymphocyte Infusion using Cryopreserved Cells for Patients with Acute Leukemia Who Relapsed Late after Hematopoietic Cell Transplantation

Research Article

Ann Hematol Oncol. 2019; 6(3): 1236.

Benefit of Granulocyte Colony-Stimulating Factor-Primed Donor Lymphocyte Infusion using Cryopreserved Cells for Patients with Acute Leukemia Who Relapsed Late after Hematopoietic Cell Transplantation

Lee YJ1,2, Moon JH1,2 and Sohn SK1,2*

¹Division of Hematology-Oncology and Internal Medicine, Kyungpook National University Hospital, Korea

²School of Medicine, Kyungpook National University, Korea

*Corresponding author: Sohn SK, Division of Hematology-Oncology, Department of Internal Medicine, Kyungpook National University Hospital, 130 Dongduk- Ro, Jung-Gu, Daegu, Korea

Received: January 03, 2019; Accepted: February 11, 2019;Published: February 18, 2019


There is no standard therapy for relapse of acute leukemia after allogeneic Hematopoietic Cell Transplantation (allo-HCT). This study evaluated the efficacy of Granulocyte Colony-Stimulating Factor (G-CSF)-Primed Donor Lymphocyte Infusion (DLI) for patients with acute leukemia who relapsed after allo-HCT. We retrospectively reviewed 255 patients who received allo-HCT for acute leukemia/myelodysplastic syndrome. They were divided into two groups based on the CD34+ cell dose they received; patients in the lower CD34+ group received less than 6×106 cells/kg and those in the higher group received over 6×106 cells/kg. No significant differences were noted between the groups with respect to overall survival, relapse-free survival, and Graft-Versus-Host Disease (GVHD)-free/relapse-free survival. Among the 93 patients with relapse after allo-HCT, 39 patients received G-CSF-primed DLI. These 93 patients were classified into early or late relapse groups as defined by the median time to relapse. In the late relapse group, the one-year overall survival was significantly higher in the DLI group than in the non-DLI group (53.4±7.4% vs. 26.7±7.4%, p=0.039), whereas there were no differences in the early relapse group. In addition, the incidence of DLI-induced GVHD did not differ between the two groups. In conclusion, treatment with G-CSF-primed DLI after allo-HCT with a limited CD34+ cell dose is a feasible and effective option, which may replace a second HCT in late relapse patients.

Keywords: Donor lymphocyte infusion; Hematopoietic stem cell transplantation; Acute leukemia; Recurrence; Granulocyte colony-stimulating factor


allo-HCT: allogeneic Hematopoietic Cell Trangrsplantation; G-CSF: Granulocyte Colony-Stimulating Factor; DLI: Donor Lymphocyte Infusion; GVHD: Graft-Versus-Host Disease; GRFS: Graft-free/Relapse-Free Survival; GVL: Graft-Versus-Leukemia; OS: Overall Survival; AML: Acute Myelogenous Leukemia; MDS: Myelodysplastic Syndrome; ALL: Acute Lymphoblastic Leukemia; KNUH: Kyungpook National University Hospital; aGVHD: acute GVHD; cGVHD: chronic GVHD; RFS: Relapse-Free Survival; PRS: Post-Relapse Survival; PBSCT: Peripheral Blood Stem Cell Transplant; Bu: Busulfan; Cy: Cytoxan; Flu: Fludarabine; GM-CSF: Granulocyte Macrophage Colony-Stimulating Factor; MTX: Methotrexate; CyA: Cyclosporine A; Tac: Tacrolimus; NRM: Non-Relapse Mortality; HR: Hazard Ratio


Allogeneic Hematopoietic Cell Transplantation (allo-HCT) is a potentially curative therapy for acute leukemia [1]. However, patients with acute leukemia who relapse after allo-HCT show poor prognosis with a median survival of 3-4 months [2]. Second allo-HCT resulted only in 10%-35% long-term survival rate, with higher treatment- related mortality. Currently, there is no standard treatment approach for these patients [3,4].

Induction of Graft-Versus-Leukemia (GVL) effects with Donor Lymphocyte Infusions (DLIs) is an attractive option for patients with relapsed hematological malignancies; however, GVL efficacy depends on disease subtype and tumor burden at the time of DLI [3,5]. Schmid et al. demonstrated an Overall Survival (OS) benefit of DLI for patients with Acute Myelogenous Leukemia (AML) who relapsed after allo-HCT (20%±3% vs. 9%±2%, p <0.001) [6]. Many experts have investigated different strategies to improve patient outcomes, such as dose-escalation of DLIs, addition of immunosuppressive agents to prevent Graft-Versus-Host Disease (GVHD), modified DLI treatment with granulocyte Colony-Stimulating Factor (G-CSF), or pre-DLI chemotherapy for cytoreduction [7-10]. Our institution reported a pilot study on the role of cytarabine with G-CSF-primed DLIs using cryopreserved cells for patients with hematological malignancies who relapsed after allo-HCT [11]. This study aimed to determine the effectiveness of cytarabine combined with G-CSFprimed DLI for patients with acute leukemia who relapsed after allo- HCT. This strategy would not only maximize donor convenience but also cost-effectiveness.

Materials and Methods

Data Collection

We conducted a retrospective review of the medical records of 255 patients who received allo-HCT for AML, Myelodysplastic Syndrome (MDS), or Acute Lymphoblastic Leukemia (ALL) between December 1998 and August 2013 at the Department of Hematology/ Oncology, Kyungpook National University Hospital (KNUH). Clinical and laboratory data were collected from electronic medical records following approval by the KNUH institutional review board.


The risk status at transplantation was based on previously published classification schemes [12]. Poor-risk cytogenetics were classified according to the revised Medical Research Council classification system for AML and the International Prognostic Scoring System for MDS [13,14]. Poor-risk cytogenetics for ALL were defined as MLL rearrangement, BCR/ABL1 translocation, hypoploidy, or complex karyotype. Graft failure was defined as the lack of myeloid engraftment in patients surviving in remission for at least 28 days after transplantation. The Keystone staging system was used to score acute GVHD (aGVHD) and chronic GVHD (cGVHD) [15,16]. Relapse was defined as the reappearance of leukemic cells in the peripheral blood, bone marrow, or extramedullary lesions after allo-HCT.

A novel composite end-point of refined GVHD-Free/Relapse- Free Survival (GRFS) was also examined, where events included grade III-IV aGVHD, systemic therapy requiring cGVHD, relapse, or death [17]. OS was calculated from the date of the first allo-HCT to the date of death, or to the last follow-up. Relapse-Free Survival (RFS) was calculated from the date of the first allo-HCT to the date of disease recurrence or to the date of death due to the disease. Post- Relapse Survival (PRS) was defined as the time from relapse posttransplantation to death or to the last follow-up [18].

Transplantation procedures

Preparative regimens for allogeneic Peripheral Blood Stem Cell Transplantation (PBSCT) included busulfan (Bu, 4mg/kg PO or 0.8mg/kg IV for 4 days) and cytoxan (Cy, 60mg/kg for 2 days) administered to 100 patients; Bu (3.2mg/kg for 2-4 days) and fludarabine (Flu, 30mg/m² for 6 days) administered to 135 patients; and total body irradiation and Cy (60mg/kg for 2 days) administered to 20 patients. PBSCs were mobilized with 10μg/kg per day G-CSF (filgrastim (Leukokine®); CJ, Co., Korea or lenograstim (Neutrogin®); Chugai Co. Ltd, Tokyo, Japan) alone (n=183, 71.8%) or in combination with a concurrent regimen of 5μg/kg per day G-CSF and 5μg/kg per day Granulocyte Macrophage Colony-Stimulating Factor (GM-CSF) (n=72, 28.2%) from the donor. Administration of G-CSF and/or GM-CSF was continued, and apheresis was repeated every morning until the targeted number of cells (6×106/kg CD34+ cells) was obtained. GVHD prophylaxis consisted of Methotrexate (MTX) and Cyclosporine A (CyA) or MTX and Tacrolimus (Tac).

Collection and infusion of donor lymphocytes

Collecting the targeted number of PBSCs (more than 6×106/ kg CD34+ cells) allowed us to cryopreserve some PBSCs, including several CD3+ cells at the time of harvest for transplantation. The extra harvested cells were cryopreserved with dimethylsulfoxide in a nitrogen tank. For those patients who relapsed after allo-HCT, DLI was promptly performed using cryopreserved cells. The CD3+ cellcount was determined by flow cytometry and used to calculate the DLI dose. Before DLI, immunosuppressive agents were discontinued and patients received pre-DLI chemotherapy with high-dose cytarabine (2g/m² twice a day on days 1, 3, and 5). The chimerism status, which was assessed by determining the variable number of tandem repeats or short tandem repeats was compared before and after DLI. All patients underwent a bone marrow examination within 60 days after DLI to assess the response, or sooner if clinically indicated.

Statistical analysis

Categorical data were analyzed using a chi-square test. Survival analysis was conducted using the Kaplan-Meier method, and both groups were compared using a log-rank test. The cumulative incidence of GVHD was calculated using the Gray method considering treatment-related mortality and relapse as competing risks. The Cox proportional regression model was used to analyze potential risk factors affecting survival. Statistical analyses were performed using the SPSS software version 18 (SPSS Inc., Chicago, IL, USA) and EZR (Saitama Medical Center, Jichi Medical University, Saitama, Japan) [19].


Patient and transplant characteristics

Two hundred and fifty-five patients were analyzed. The median infused cell doses were as follows: mononuclear cell number 7.94×108/ kg (range: 0.36-25.12), CD34+ cell number 5.13×106/kg (range: 0.46- 20.6), and CD3+ cell number 2.82×108/kg (range: 0.05-10.0). Patients were reclassified into two groups according to the targeted CD34+ cell dose (6×106/kg) based on the KNUH protocol. The lower CD34+ group (n=165, 64.7%) included patients who underwent allo-HCT with CD34+ cell dose <6×106/kg, and the higher CD34+ group (n=90, 35.3%) included patients who underwent allo-HCT with CD34+ cell dose =6×106/kg. Patient characteristics are summarized in Table 1. No statistically significant differences between the two groups were found in the transplantation outcomes, such as the incidence of aGVHD, cGVHD, and relapse rate (Table 2).