- Email: [email protected]
Adequate Engraftment With Lower Hematopoietic Stem Cell Dose
Journal Pre-proof Adequate Engraftment with Lower Hematopoietic Stem Cell Dose Preethi Jeyaraman, DM, Pronamee Borah, MBBS, Nitin Dayal, MD, Sangeeta Pathak, MD, Rahul Naithani, DM, FRCP (Edin) PII:
S2152-2650(20)30003-3
DOI:
https://doi.org/10.1016/j.clml.2019.12.018
Reference:
CLML 1501
To appear in:
Clinical Lymphoma, Myeloma and Leukemia
Received Date: 17 November 2019 Revised Date:
29 December 2019
Accepted Date: 31 December 2019
Please cite this article as: Jeyaraman P, Borah P, Dayal N, Pathak S, Naithani R, Adequate Engraftment with Lower Hematopoietic Stem Cell Dose, Clinical Lymphoma, Myeloma and Leukemia (2020), doi: https://doi.org/10.1016/j.clml.2019.12.018. This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. © 2020 Elsevier Inc. All rights reserved.
Micro abstract
Data for 108 patients with multiple myeloma and lymphoma who received a stem cell dose less than 2 x 106/kg with those who received higher dose was compared.
Neutrophil engraftment, platelet engraftment, length of hospital stay and incidence of proven bacterial infections were similar in both groups. ASCT can be safely performed even with lower HSC dose in non-cryopreserved setting.
Adequate Engraftment with Lower Hematopoietic Stem Cell Dose
Preethi Jeyaraman, DM1; Pronamee Borah, MBBS1; Nitin Dayal, MD2, Sangeeta Pathak, MD3, Rahul Naithani, DM, FRCP (Edin)1
1
Division of Hematology & Bone Marrow Transplantation, 2 Department of Lab Medicine,
3
Department of Transfusion Medicine, Max Super-specialty Hospital, Saket, New Delhi, India.
Word Count-1606, Table: 1
Conflict-of-interest statement: No financial relationships to disclose.
Corresponding Author Dr. Rahul Naithani, MD, DM, FRCP (Edin) Hematology & Bone Marrow Transplantation Max Super-specialty Hospital, Delhi, India-110017 Email: [email protected], Fax: +91 11 2223 5563
Abstract
Background: Adequate hematopoietic stem cell dose is required to proceed with autologous stem cell transplant (ASCT).
Methods: We conducted a retrospective analysis of 108 patients with multiple myeloma and lymphoma who underwent ASCT with non-cryopreserved stem cells at our center. Data was compared for patients who received a stem cell dose less than 2 x 106/kg with those who received higher dose.
Results: The median CD34 dose harvested in lesser dose group was 1.76 x 106cells / kg (1.22 to 1.97 x 106 cells / kg). Mean CD34 dose of the whole group was 4.96 + 4.2 x 106cells/kg. Neutrophil engraftment was similar in both groups (12 days vs 11 days) (p=0.065). Similarly, platelet engraftment occurred in 12 vs 11 days in both groups (p=0.017). Length of hospital stay was similar in both groups. There was no significant difference in the incidence of proven bacterial infections between the 2 groups. There was no TRM in lower dose group.
Conclusions: ASCT can be safely performed even with lower HSC dose in non-cryopreserved setting.
Key words: ASCT; non-cryopreserved; stem cell dose; engraftment, infection; myeloma; lymphoma
Introduction Autologous hematopoietic stem cell transplantation (ASCT) is an important component in treatment of patients with multiple myelomai and lymphoma.ii Peripheral blood stem cells (PBSCs) are the main source used to support autologous HSC transplants (ASCT).iii Lutfi et al, have documented that smaller HSC dose is associated with delayed engraftment.iv Others have also reported the impact of infused CD34+dose and delayed engraftment after ASCT.v A consensus published by the American Society for Blood and Marrow Transplantation recommends collecting a minimum dose of 2 × 106 CD34+ cells/kg to perform ASCT, but the decision to accept collections of between 1 × 106 and 2 × 106 CD34+ cells/kg can be individualized according to the circumstances of each patient.vi This data, however, is based on cryopreserved hematopoietic stem cells (HSCs). Appropriate minimum HSC dose in noncryopreserved setting is still not defined. We have earlier demonstrated that non-cryopreserved stem cells are effective in myeloma and lymphoma.vii An inverse relationship between HSC dose and platelet engraftment has been documented.viii Our study looks at outcomes of autologous HSCT for multiple myeloma and lymphoma when HSC dose was less than 2 × 106 CD34+ cells/kg.
Patients & Methods
Patients were nursed in HEPA filtered air-conditioned single rooms with reverse barrier nursing. Patients were kept in isolation from start of conditioning till engraftment. All persons entering the room used shoe covers, put on a face mask and cap, and washed their hands thoroughly or
used antiseptic handwash antimicrobial prophylaxis. All patients received oral ciprofloxacin, fluconazole and valacyclovir as antibacterial, antifungal and antiviral prophylaxis, respectively. Fluconazole and valacyclovir were stopped on day 28. Cotrimoxazole prophylaxis was not used after HSC infusion. Hemoglobin was maintained above 7 g/dl and platelet counts above 10 x 109/l in afebrile patients and > 20 x 109/l in febrile patients. Fever was defined as a single temperature of ≥ 101 F or >100.4 F lasting for more than 1 hour. Any febrile episode was treated with broad-spectrum antibiotics. First-line antibiotic cover during conditioning consisted of piperacillin–tazobactam or cefoperazone-sulbactum and amikacin. Any febrile episode was taken ass infective episode and treated. This was modified later depending on microbiological information or clinical evolution.
Bone Marrow Transplant Protocol Informed written consent was obtained from all patients. A central venous access was put in place in all patients. Peripheral blood stem cell apheresis was performed using Hemonetics MCS plus or Cobe Spectra apheresis machine. Stem cell mobilization was done with Granulocyte Colony Stimulating Factor (GCSF) 10 ug/kg/day followed by stem cell mobilization on day 5. In patients with risk factors for poor mobilization (like thrombocytopenia, multiple prior lines of therapy, therapy with lenalidomide and melphalan for myeloma patients, prior radiation to marrow bearing areas, treatment duration prior to transplant, bone marrow involvement with disease and cellularity) pre-emptive plerixafor 0.24 mg/kg was given 11 hours prior to 1st mobilization. Prior to 2014 when plerixafor became available in India, these patients underwent chemo-mobilisation. Two to three apheresis sessions were performed before declaring mobilization failure.
The harvested stem cells were stored in a conventional blood bank refrigerator at 4°C.vii Stem cell yield of the harvest was determined by CD34 cell enumeration using ISHAGE protocol.ix The goal for apheresis was to collect an average of 2 x 106/kg CD34 stem cells. Patients received G-CSF 300 micrograms once a day starting on Day +6 after infusion of stem cells until the time of engraftment. Neutrophil engraftment was defined as the first of 3 consecutive days with achievement of absolute neutrophil count of ≥ 500/mm3 and no subsequent decline. Platelet engraftment was defined as the first of 3 consecutive values of platelet count ≥ 20,000/cm3 with transfusion independence. All patients remained hospitalized until engraftment and until the time deemed clinically suitable for discharge. Discharge criteria were neutrophil engraftment, absence of infection and ability to eat and drink.
Results
This is a retrospective analysis of 108 patients with multiple myeloma (84) and lymphoma (24) who underwent ASCT at our institute. All lymphoma patients received conditioning with BEAM protocol. Patients with myeloma received melphalan at a dose of 200 mg/m2 or 140 mg/m2 depending on their renal function. Patients were grouped based on their stem cell dose based on the cut off of 2 x 106/kg. The effect on neutrophil and platelet engraftment and length of hospital stay. Effect of stem cell dose on day 100 transplant related mortality (TRM) and incidence of proven infections were analysed. Median age was 53 years (range: 14 to 68 years) with a male: female ratio of 1.5.Fourteen patients (8 Myeloma, 6 lymphoma) had HSC dose < 2x 106/kg.G-CSF, at a dose of 10
microgram/kg subcutaneous once daily was used in 11 patients, plerixafor in 2 and chemomobilisation with cyclophosphamide was used in one patient. The HSC dose harvested in lesser dose group was 1.76x 106cells/kg (1.22 to 1.97 x 106cells/kg). One patient with refractory multiple myeloma was transplanted with stem cell dose of 1.52 million (despite plerixafor and 2 apheresis sessions). She engrafted well and continues to be in remission at 2.5 years from transplant. One patient with lymphoma was transplanted with stem cell dose of 1.22 million/kg and engrafted well. Table I shows general characteristics of study cohort. Mean CD34 dose of the whole group was 4.96 + 4.2 x 106cells/kg.
Neutrophil engraftment was similar in both groups (12 days vs 11 days) (p=0.065). Similarly, platelet engraftment occurred in 12 vs 11 days in both groups (p=0.017). Hospital stay was similar in both groups. There was no significant difference in the incidence of proven bacterial infections between the 2 groups. There was no TRM in lower dose group. Fourteen patients had stem cell dose < 2 x 106/ kg. The median age of this group was 56 years (range 36 to 68 years)- 8 males and 6 females. Median number of apheresis sessions were 2 in these patients. Eight patients had myeloma and 6 patients had lymphoma. Prior chemotherapy regimens used include gemcitabine dexamethasone cisplatin in 2, rituximab ifosfamide carboplatine and etoposide in 2, Daratumumab in 1, vincristine, doxorubicine, dexamethasone in 1, dose adjusted etoposide, prednisolone, vincristine, cyclophosphamisde, doxorubicin in one, bendamustine, rituximab in one and bortezomib, cyclophosphamide, dexamethasone in 5 patients. Eight patients were in complete remission, 5 in partial remission and 1 in very good partial response(myeloma). One patient was HIV positive.
Discussion Adequate HSC dose is a prerequisite to safely proceed with autologous HSCT. In autologous HSCT, our target was 2 million/kg cell dose. A minimum stem cell dose threshold in noncryopreserved setting (which is common in India) has not been identified. Although 2 × 106 CD34+ cells/kg is generally accepted as the minimum goal, successful transplantation has occurred at much lower doses as mentioned in the ASBMT guidelines. Most of our patients did have stem cell doses close to 2 million/kg. If that dose was achieved, we did not attempt another harvest to save on harvest + cryopreservation cost as we are price sensitive country. Even though it is presumed that higher stem cell dose will lead to an early engraftmentii,iii,iv, that’s not the case always. A study of 112 patients revealed that with an increase in CD34+ stem cell dose by 1 × 106/kg reduced the neutrophil engraftment time by only 3 h and 50 min.x Conditioning chemotherapy, bacteremia, G-CSF dose/kg body weight and increasing age had no impact on time to neutrophil recovery. There are valid concerns that stem cells were kept at 4 degree in refrigerator. In lymphoma patients, the BEAM chemotherapy takes 6 days. That means we kept the harvested stem cells for 7 days which is generally not a routine. In lymphoma patients we start BCNU on day of harvest itself which saves us one day. It has been shown earlier that liquid storage of stem cell harvest at 4 degree C upto 8 days results in timely engraftment.xi We have earlier shown that patients undergoing ASCT with non-cryopreserved stem cells showed adequate engraftment and
acceptable outcomes.vii We did not check CD34 cells dose as well as viability before infusion. But adequate engraftment in our patients suggest that viability was not an issue. In addition to the dose of peripheral blood stem cells infused, other treatment-related factors may influence the time to haematopoietic recovery. These include the conditioning chemotherapy regimen and use of cytokine support in the form of granulocyte colony-stimulating factor (GCSF). Many patients are poor mobilisers and are denied benefit of HSCT when HSC dose is < 2 million/kg. We demonstrate that adequate engraftment can be achieved even when HSC dose was lesser. We cannot confirm if same will apply in setting of cryopreservation of stem cells. All 14 patients engrafted in reasonable time frame. There was no difference in engraftment kinetics between patients having < 2million/kg or > 2 million/kg stem cell dose. This small data may suggest that for non-cryopreserved hematopoietic stem cell smaller dose may be sufficient. This may make many more patients eligible for HSCT.
We are not discussing progression free survival and other outcomes as these depend on multiple clinical variables. Main limitation of our data is small sample size and retrospective nature of analysis. We did not measure CD 34 counts after storage and pre-storage counts were taken as measure of viable counts. There is no consensus if viable CD 34 count predicts engraftment kinetics. x,xii Initial trends in the outcome in this study are encouraging. This small data will encourage other hematologists across world to start performing lower dose HSCTs. Overall, with lower HSC dose many more patients can be benefitted by ASCT who were earlier declared unfit due to HSC dose.
Conclusion Autologous HSCT can be safely performed with non-cryopreserved hematopoietic stem cell dose less than 2 million/kg.
References i
Jackson GH, Davies FE, Pawlyn C, et al. Response-adapted intensification with
cyclophosphamide, bortezomib and dexamethasone versus no intensification in patients with newly diagnosed multiple myeloma (Myeloma XI): a multicentre, open-label, randomised, phase 3 trial. Lancet Haematol 2019; published online Oct 14. https://doi.org/10.1016/ S23523026(19)30167-X. ii
Sureda A, Chabannon C, Masszi T, Pohlreich D, Scheid C, Thieblemont C et al. Analysis of
data collected in the European Society for Blood and Marrow Transplantation (EBMT) Registry on a cohort of lymphoma patients receiving plerixafor. Bone Marrow Transplant. 2019 Sep 30. doi: 10.1038/s41409-019-0693-z. iii
Yilmaz Ü, Salim O, Yücel OK, Iltar U, Ündar L. Comparison of Various Hema-poietic Stem
Cell Mobilization Regimens in Patients with Lymphoma and Myeloma. Clin Lab. 2019 Oct 1;65(10). doi: 10.7754/Clin.Lab.2019.190214. iv
Lutfi F, Skel-n Iv WP, Wang Y, Rosenau E, Farhadfar N, Murthy H et al. Clinical predic-rs of
delayed engraftment in au-logous hema-poietic cell transplant recipients. Hema-l Oncol Stem Cell Ther. 2019 Oct 10. pii: S1658-3876(19)30072-X. doi: 10.1016/j.hemonc.2019.08.003. v
Walling-n-Beddoe CT, Gottlieb DJ, Garvin F, An-nenas V,387Sar-r MM. Failure - achieve a
threshold dose of CD34+CD110+ progeni-r cells in the graft predicts delayed platelet
engraftment after au-logous stem cell transplantation for multiple myeloma. Biol Blood Marrow Transplant 2009;15:1386–93. vi
Giralt S, Costa L, Schriber J, Dipersio J, Maziarz R, McCarty J, et al. Optimizing au-logous
stem cell mobilization strategies - improve patient outcomes: consensus guidelines and recommendations. Biol Blood Marrow Transplant. 2014;20(3):295–308. vii
Naithani R, Dayal N, Pathak S, Rai R. Hema-poietic stem cell transplantation using non-
cryopreserved peripheral blood stem cells graft is effective in multiple myeloma and lymphoma. Bone Marrow Transplant. 2018 Sep;53(9):1198-1200. viii
Stiff PJ, Micallef I, Nademanee AP, Stadtmauer EA, Maziarz RT, Bolwell BJ, et al.
Transplanted CD34(+) cell dose is associated with long-term platelet count recoveryfollowing au-logous peripheral blood stem cell transplant in patients with non-Hodgkin lymphoma or multiple myeloma. Biol Blood Marrow Transplant 2011;17:1146–53. ix
Naithani R, Dayal N, Dixit G. Single Versus Dual Platform Analysis for Hema-poietic Stem
Cell Enumeration Using ISHAGE Protocol. Indian J Hematol Blood Transfus. 2017 Sep;33(3):370-374. x
Nath K, Boles R, McCutchan A, Vangaveti V, Birchley A, Irving I. The relationship
between CD34+ stem cell dose and time - neutrophil recovery in au-logous haema-poietic stem cell recipients-A single centre experience. Transfus Apher Sci. 2018 Aug;57(4):532-536. xi
Liquid s-rage of stem cell harvest at 4 degree C up- 8 days results in timely engraftment.
https://academic.oup.com/annonc/article/18/4/623/134012 (accessed 29 Dec 2019) xii
Morgenstern DA, Ahsan G, Brocklesby M, Ings S, Balsa C, Veys P, et al. Post-thaw viability
of cryopreserved peripheral blood stem cells (PBSC) does not guarantee functional activity:
important implications for quality assurance of stem cell transplant programmes. Br J Haema-l 2016;174:942–51.
Table I: General Transplant Characteristics of Study Cohort CD 34 <2 x106/kg
CD 34>2 x106/kg
p-value 0.047
Number of patients Multiple Myeloma
8
76
Lymphoma
6
18
CR
8
45
PR
6
36
Active
0
3
G-CSF
11
39
Plerixafor + GCSF
2
34
Cyclophosphamide + G-CSF
1
21
CD 34 Dose (x 106/kg)
1.72
5.40
0.000
Neutrophil Engraftment
12 (10-14) Days
11 (9-35) Days
0.065
12 (10-23) Days
11 (8-65) Days
0.017
Remission Status at Transplant 0.68
Mobilisation Regimes 0.034
[Median (Range)] Platelet Engraftment [Median (Range)]
Proven Bacterial Infections
3
28
0.291
Hospital Stay (From stem cell infusion)
21 (16 - 36) Days
19 (12 - 61) Days
0.227
Clinical Practice Points 1. Autologous hematopoietic stem cell transplant is feasible with lower stem cell dose in myeloma and lymphoma. 2. This is valid in non-cryopreserved setting.
S2152-2650(20)30003-3
DOI:
https://doi.org/10.1016/j.clml.2019.12.018
Reference:
CLML 1501
To appear in:
Clinical Lymphoma, Myeloma and Leukemia
Received Date: 17 November 2019 Revised Date:
29 December 2019
Accepted Date: 31 December 2019
Please cite this article as: Jeyaraman P, Borah P, Dayal N, Pathak S, Naithani R, Adequate Engraftment with Lower Hematopoietic Stem Cell Dose, Clinical Lymphoma, Myeloma and Leukemia (2020), doi: https://doi.org/10.1016/j.clml.2019.12.018. This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. © 2020 Elsevier Inc. All rights reserved.
Micro abstract
Data for 108 patients with multiple myeloma and lymphoma who received a stem cell dose less than 2 x 106/kg with those who received higher dose was compared.
Neutrophil engraftment, platelet engraftment, length of hospital stay and incidence of proven bacterial infections were similar in both groups. ASCT can be safely performed even with lower HSC dose in non-cryopreserved setting.
Adequate Engraftment with Lower Hematopoietic Stem Cell Dose
Preethi Jeyaraman, DM1; Pronamee Borah, MBBS1; Nitin Dayal, MD2, Sangeeta Pathak, MD3, Rahul Naithani, DM, FRCP (Edin)1
1
Division of Hematology & Bone Marrow Transplantation, 2 Department of Lab Medicine,
3
Department of Transfusion Medicine, Max Super-specialty Hospital, Saket, New Delhi, India.
Word Count-1606, Table: 1
Conflict-of-interest statement: No financial relationships to disclose.
Corresponding Author Dr. Rahul Naithani, MD, DM, FRCP (Edin) Hematology & Bone Marrow Transplantation Max Super-specialty Hospital, Delhi, India-110017 Email: [email protected], Fax: +91 11 2223 5563
Abstract
Background: Adequate hematopoietic stem cell dose is required to proceed with autologous stem cell transplant (ASCT).
Methods: We conducted a retrospective analysis of 108 patients with multiple myeloma and lymphoma who underwent ASCT with non-cryopreserved stem cells at our center. Data was compared for patients who received a stem cell dose less than 2 x 106/kg with those who received higher dose.
Results: The median CD34 dose harvested in lesser dose group was 1.76 x 106cells / kg (1.22 to 1.97 x 106 cells / kg). Mean CD34 dose of the whole group was 4.96 + 4.2 x 106cells/kg. Neutrophil engraftment was similar in both groups (12 days vs 11 days) (p=0.065). Similarly, platelet engraftment occurred in 12 vs 11 days in both groups (p=0.017). Length of hospital stay was similar in both groups. There was no significant difference in the incidence of proven bacterial infections between the 2 groups. There was no TRM in lower dose group.
Conclusions: ASCT can be safely performed even with lower HSC dose in non-cryopreserved setting.
Key words: ASCT; non-cryopreserved; stem cell dose; engraftment, infection; myeloma; lymphoma
Introduction Autologous hematopoietic stem cell transplantation (ASCT) is an important component in treatment of patients with multiple myelomai and lymphoma.ii Peripheral blood stem cells (PBSCs) are the main source used to support autologous HSC transplants (ASCT).iii Lutfi et al, have documented that smaller HSC dose is associated with delayed engraftment.iv Others have also reported the impact of infused CD34+dose and delayed engraftment after ASCT.v A consensus published by the American Society for Blood and Marrow Transplantation recommends collecting a minimum dose of 2 × 106 CD34+ cells/kg to perform ASCT, but the decision to accept collections of between 1 × 106 and 2 × 106 CD34+ cells/kg can be individualized according to the circumstances of each patient.vi This data, however, is based on cryopreserved hematopoietic stem cells (HSCs). Appropriate minimum HSC dose in noncryopreserved setting is still not defined. We have earlier demonstrated that non-cryopreserved stem cells are effective in myeloma and lymphoma.vii An inverse relationship between HSC dose and platelet engraftment has been documented.viii Our study looks at outcomes of autologous HSCT for multiple myeloma and lymphoma when HSC dose was less than 2 × 106 CD34+ cells/kg.
Patients & Methods
Patients were nursed in HEPA filtered air-conditioned single rooms with reverse barrier nursing. Patients were kept in isolation from start of conditioning till engraftment. All persons entering the room used shoe covers, put on a face mask and cap, and washed their hands thoroughly or
used antiseptic handwash antimicrobial prophylaxis. All patients received oral ciprofloxacin, fluconazole and valacyclovir as antibacterial, antifungal and antiviral prophylaxis, respectively. Fluconazole and valacyclovir were stopped on day 28. Cotrimoxazole prophylaxis was not used after HSC infusion. Hemoglobin was maintained above 7 g/dl and platelet counts above 10 x 109/l in afebrile patients and > 20 x 109/l in febrile patients. Fever was defined as a single temperature of ≥ 101 F or >100.4 F lasting for more than 1 hour. Any febrile episode was treated with broad-spectrum antibiotics. First-line antibiotic cover during conditioning consisted of piperacillin–tazobactam or cefoperazone-sulbactum and amikacin. Any febrile episode was taken ass infective episode and treated. This was modified later depending on microbiological information or clinical evolution.
Bone Marrow Transplant Protocol Informed written consent was obtained from all patients. A central venous access was put in place in all patients. Peripheral blood stem cell apheresis was performed using Hemonetics MCS plus or Cobe Spectra apheresis machine. Stem cell mobilization was done with Granulocyte Colony Stimulating Factor (GCSF) 10 ug/kg/day followed by stem cell mobilization on day 5. In patients with risk factors for poor mobilization (like thrombocytopenia, multiple prior lines of therapy, therapy with lenalidomide and melphalan for myeloma patients, prior radiation to marrow bearing areas, treatment duration prior to transplant, bone marrow involvement with disease and cellularity) pre-emptive plerixafor 0.24 mg/kg was given 11 hours prior to 1st mobilization. Prior to 2014 when plerixafor became available in India, these patients underwent chemo-mobilisation. Two to three apheresis sessions were performed before declaring mobilization failure.
The harvested stem cells were stored in a conventional blood bank refrigerator at 4°C.vii Stem cell yield of the harvest was determined by CD34 cell enumeration using ISHAGE protocol.ix The goal for apheresis was to collect an average of 2 x 106/kg CD34 stem cells. Patients received G-CSF 300 micrograms once a day starting on Day +6 after infusion of stem cells until the time of engraftment. Neutrophil engraftment was defined as the first of 3 consecutive days with achievement of absolute neutrophil count of ≥ 500/mm3 and no subsequent decline. Platelet engraftment was defined as the first of 3 consecutive values of platelet count ≥ 20,000/cm3 with transfusion independence. All patients remained hospitalized until engraftment and until the time deemed clinically suitable for discharge. Discharge criteria were neutrophil engraftment, absence of infection and ability to eat and drink.
Results
This is a retrospective analysis of 108 patients with multiple myeloma (84) and lymphoma (24) who underwent ASCT at our institute. All lymphoma patients received conditioning with BEAM protocol. Patients with myeloma received melphalan at a dose of 200 mg/m2 or 140 mg/m2 depending on their renal function. Patients were grouped based on their stem cell dose based on the cut off of 2 x 106/kg. The effect on neutrophil and platelet engraftment and length of hospital stay. Effect of stem cell dose on day 100 transplant related mortality (TRM) and incidence of proven infections were analysed. Median age was 53 years (range: 14 to 68 years) with a male: female ratio of 1.5.Fourteen patients (8 Myeloma, 6 lymphoma) had HSC dose < 2x 106/kg.G-CSF, at a dose of 10
microgram/kg subcutaneous once daily was used in 11 patients, plerixafor in 2 and chemomobilisation with cyclophosphamide was used in one patient. The HSC dose harvested in lesser dose group was 1.76x 106cells/kg (1.22 to 1.97 x 106cells/kg). One patient with refractory multiple myeloma was transplanted with stem cell dose of 1.52 million (despite plerixafor and 2 apheresis sessions). She engrafted well and continues to be in remission at 2.5 years from transplant. One patient with lymphoma was transplanted with stem cell dose of 1.22 million/kg and engrafted well. Table I shows general characteristics of study cohort. Mean CD34 dose of the whole group was 4.96 + 4.2 x 106cells/kg.
Neutrophil engraftment was similar in both groups (12 days vs 11 days) (p=0.065). Similarly, platelet engraftment occurred in 12 vs 11 days in both groups (p=0.017). Hospital stay was similar in both groups. There was no significant difference in the incidence of proven bacterial infections between the 2 groups. There was no TRM in lower dose group. Fourteen patients had stem cell dose < 2 x 106/ kg. The median age of this group was 56 years (range 36 to 68 years)- 8 males and 6 females. Median number of apheresis sessions were 2 in these patients. Eight patients had myeloma and 6 patients had lymphoma. Prior chemotherapy regimens used include gemcitabine dexamethasone cisplatin in 2, rituximab ifosfamide carboplatine and etoposide in 2, Daratumumab in 1, vincristine, doxorubicine, dexamethasone in 1, dose adjusted etoposide, prednisolone, vincristine, cyclophosphamisde, doxorubicin in one, bendamustine, rituximab in one and bortezomib, cyclophosphamide, dexamethasone in 5 patients. Eight patients were in complete remission, 5 in partial remission and 1 in very good partial response(myeloma). One patient was HIV positive.
Discussion Adequate HSC dose is a prerequisite to safely proceed with autologous HSCT. In autologous HSCT, our target was 2 million/kg cell dose. A minimum stem cell dose threshold in noncryopreserved setting (which is common in India) has not been identified. Although 2 × 106 CD34+ cells/kg is generally accepted as the minimum goal, successful transplantation has occurred at much lower doses as mentioned in the ASBMT guidelines. Most of our patients did have stem cell doses close to 2 million/kg. If that dose was achieved, we did not attempt another harvest to save on harvest + cryopreservation cost as we are price sensitive country. Even though it is presumed that higher stem cell dose will lead to an early engraftmentii,iii,iv, that’s not the case always. A study of 112 patients revealed that with an increase in CD34+ stem cell dose by 1 × 106/kg reduced the neutrophil engraftment time by only 3 h and 50 min.x Conditioning chemotherapy, bacteremia, G-CSF dose/kg body weight and increasing age had no impact on time to neutrophil recovery. There are valid concerns that stem cells were kept at 4 degree in refrigerator. In lymphoma patients, the BEAM chemotherapy takes 6 days. That means we kept the harvested stem cells for 7 days which is generally not a routine. In lymphoma patients we start BCNU on day of harvest itself which saves us one day. It has been shown earlier that liquid storage of stem cell harvest at 4 degree C upto 8 days results in timely engraftment.xi We have earlier shown that patients undergoing ASCT with non-cryopreserved stem cells showed adequate engraftment and
acceptable outcomes.vii We did not check CD34 cells dose as well as viability before infusion. But adequate engraftment in our patients suggest that viability was not an issue. In addition to the dose of peripheral blood stem cells infused, other treatment-related factors may influence the time to haematopoietic recovery. These include the conditioning chemotherapy regimen and use of cytokine support in the form of granulocyte colony-stimulating factor (GCSF). Many patients are poor mobilisers and are denied benefit of HSCT when HSC dose is < 2 million/kg. We demonstrate that adequate engraftment can be achieved even when HSC dose was lesser. We cannot confirm if same will apply in setting of cryopreservation of stem cells. All 14 patients engrafted in reasonable time frame. There was no difference in engraftment kinetics between patients having < 2million/kg or > 2 million/kg stem cell dose. This small data may suggest that for non-cryopreserved hematopoietic stem cell smaller dose may be sufficient. This may make many more patients eligible for HSCT.
We are not discussing progression free survival and other outcomes as these depend on multiple clinical variables. Main limitation of our data is small sample size and retrospective nature of analysis. We did not measure CD 34 counts after storage and pre-storage counts were taken as measure of viable counts. There is no consensus if viable CD 34 count predicts engraftment kinetics. x,xii Initial trends in the outcome in this study are encouraging. This small data will encourage other hematologists across world to start performing lower dose HSCTs. Overall, with lower HSC dose many more patients can be benefitted by ASCT who were earlier declared unfit due to HSC dose.
Conclusion Autologous HSCT can be safely performed with non-cryopreserved hematopoietic stem cell dose less than 2 million/kg.
References i
Jackson GH, Davies FE, Pawlyn C, et al. Response-adapted intensification with
cyclophosphamide, bortezomib and dexamethasone versus no intensification in patients with newly diagnosed multiple myeloma (Myeloma XI): a multicentre, open-label, randomised, phase 3 trial. Lancet Haematol 2019; published online Oct 14. https://doi.org/10.1016/ S23523026(19)30167-X. ii
Sureda A, Chabannon C, Masszi T, Pohlreich D, Scheid C, Thieblemont C et al. Analysis of
data collected in the European Society for Blood and Marrow Transplantation (EBMT) Registry on a cohort of lymphoma patients receiving plerixafor. Bone Marrow Transplant. 2019 Sep 30. doi: 10.1038/s41409-019-0693-z. iii
Yilmaz Ü, Salim O, Yücel OK, Iltar U, Ündar L. Comparison of Various Hema-poietic Stem
Cell Mobilization Regimens in Patients with Lymphoma and Myeloma. Clin Lab. 2019 Oct 1;65(10). doi: 10.7754/Clin.Lab.2019.190214. iv
Lutfi F, Skel-n Iv WP, Wang Y, Rosenau E, Farhadfar N, Murthy H et al. Clinical predic-rs of
delayed engraftment in au-logous hema-poietic cell transplant recipients. Hema-l Oncol Stem Cell Ther. 2019 Oct 10. pii: S1658-3876(19)30072-X. doi: 10.1016/j.hemonc.2019.08.003. v
Walling-n-Beddoe CT, Gottlieb DJ, Garvin F, An-nenas V,387Sar-r MM. Failure - achieve a
threshold dose of CD34+CD110+ progeni-r cells in the graft predicts delayed platelet
engraftment after au-logous stem cell transplantation for multiple myeloma. Biol Blood Marrow Transplant 2009;15:1386–93. vi
Giralt S, Costa L, Schriber J, Dipersio J, Maziarz R, McCarty J, et al. Optimizing au-logous
stem cell mobilization strategies - improve patient outcomes: consensus guidelines and recommendations. Biol Blood Marrow Transplant. 2014;20(3):295–308. vii
Naithani R, Dayal N, Pathak S, Rai R. Hema-poietic stem cell transplantation using non-
cryopreserved peripheral blood stem cells graft is effective in multiple myeloma and lymphoma. Bone Marrow Transplant. 2018 Sep;53(9):1198-1200. viii
Stiff PJ, Micallef I, Nademanee AP, Stadtmauer EA, Maziarz RT, Bolwell BJ, et al.
Transplanted CD34(+) cell dose is associated with long-term platelet count recoveryfollowing au-logous peripheral blood stem cell transplant in patients with non-Hodgkin lymphoma or multiple myeloma. Biol Blood Marrow Transplant 2011;17:1146–53. ix
Naithani R, Dayal N, Dixit G. Single Versus Dual Platform Analysis for Hema-poietic Stem
Cell Enumeration Using ISHAGE Protocol. Indian J Hematol Blood Transfus. 2017 Sep;33(3):370-374. x
Nath K, Boles R, McCutchan A, Vangaveti V, Birchley A, Irving I. The relationship
between CD34+ stem cell dose and time - neutrophil recovery in au-logous haema-poietic stem cell recipients-A single centre experience. Transfus Apher Sci. 2018 Aug;57(4):532-536. xi
Liquid s-rage of stem cell harvest at 4 degree C up- 8 days results in timely engraftment.
https://academic.oup.com/annonc/article/18/4/623/134012 (accessed 29 Dec 2019) xii
Morgenstern DA, Ahsan G, Brocklesby M, Ings S, Balsa C, Veys P, et al. Post-thaw viability
of cryopreserved peripheral blood stem cells (PBSC) does not guarantee functional activity:
important implications for quality assurance of stem cell transplant programmes. Br J Haema-l 2016;174:942–51.
Table I: General Transplant Characteristics of Study Cohort CD 34 <2 x106/kg
CD 34>2 x106/kg
p-value 0.047
Number of patients Multiple Myeloma
8
76
Lymphoma
6
18
CR
8
45
PR
6
36
Active
0
3
G-CSF
11
39
Plerixafor + GCSF
2
34
Cyclophosphamide + G-CSF
1
21
CD 34 Dose (x 106/kg)
1.72
5.40
0.000
Neutrophil Engraftment
12 (10-14) Days
11 (9-35) Days
0.065
12 (10-23) Days
11 (8-65) Days
0.017
Remission Status at Transplant 0.68
Mobilisation Regimes 0.034
[Median (Range)] Platelet Engraftment [Median (Range)]
Proven Bacterial Infections
3
28
0.291
Hospital Stay (From stem cell infusion)
21 (16 - 36) Days
19 (12 - 61) Days
0.227
Clinical Practice Points 1. Autologous hematopoietic stem cell transplant is feasible with lower stem cell dose in myeloma and lymphoma. 2. This is valid in non-cryopreserved setting.