The effect of cryopreserved and noncryopreserved stem cells on the outcome of autologous stem-cell transplantation in multiple myeloma patients: A single-center experience

Ayşe Uysal; Mehmet A Erkurt; İrfan Kuku; Emin Kaya; İlhami Berber; Ahmet Sarıcı; Soykan Biçim; Emine Hidayet; Ahmet Kaya; Mustafa Merter

doi:10.4103/ejh.ejh_2_22

ORIGINAL ARTICLE

Year : 2022 | Volume : 47 | Issue : 3 | Page : 181-186

The effect of cryopreserved and noncryopreserved stem cells on the outcome of autologous stem-cell transplantation in multiple myeloma patients: A single-center experience

Ayşe Uysal¹, Mehmet A Erkurt², İrfan Kuku², Emin Kaya², İlhami Berber², Ahmet Sarıcı², Soykan Biçim², Emine Hidayet², Ahmet Kaya², Mustafa Merter¹
¹ Department of Hematology, Fırat University School of Medicine, Elazığ, Turkey
² Department of Adult Hematology, Turgut Ozal Medical Center, Inonu University, Malatya, Turkey

Date of Submission	09-Jan-2022
Date of Acceptance	30-Jan-2022
Date of Web Publication	03-Jan-2023

Correspondence Address:
Mehmet A Erkurt
Department of Adult Hematology, Turgut Ozal Medical Center, Inonu University, Malatya
Turkey

Source of Support: None, Conflict of Interest: None

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DOI: 10.4103/ejh.ejh_2_22

Abstract

Background The CD34+ stem cells are either noncryopreserved (non-CP) or cryopreserved (CP) in autologous stem-cell transplantation (ASCT). Some retrospective studies have shown that engraftment failure and engraftment rate are similar in CP cells and infusion reactions are lower in CP cells due to the absence of dimethyl sulfoxide. Objective In this study, we presented our clinical experience comparing the outcomes and safety of ASCT with CP and non-CP stem cells. Patients and methods A total of 163 patients were enrolled between January 2019 and June 2021. Duration of neutrophil/platelet engraftment, rates of infusion-related reactions, febrile neutropenia, and duration of hospitalization were compared between the CP and non-CP groups. Results Fifty five (33.7%) received CP cells, 108 (66.3%) received non-CP cells. The median dose of CD34+ cells was similar in both groups (P=0.755). The median duration of neutrophil and platelet engraftment was not statistically significantly different in CP and non-CP groups (P=0.896 and 0.183, respectively). No statistical difference was observed in the median duration of hospitalization between the two groups [CP: 16 (13–26) vs. non-CP: 15 (11–31) days, P=0.124]. The febrile neutropenia rate was higher in the CP group, but there was no statistical difference between the two groups (CP: 56.4% vs. non-CP, 48.1%, P=0.301). The rates of infusion-related reaction such as nausea, vomiting, and rash were higher in the CP group (21.8 vs. 12%), with no statistically significant difference (P=0.159). Conclusion Non-CP cells have similar outcomes to CP cells and lower toxicity than CP cells, which are safe and effective in ASCT.

Keywords: autologous stem-cell transplantation, cryopreserved, engraftment, infusion-related reaction

How to cite this article:
Uysal A, Erkurt MA, Kuku &, Kaya E, Berber &, Sarıcı A, Biçim S, Hidayet E, Kaya A, Merter M. The effect of cryopreserved and noncryopreserved stem cells on the outcome of autologous stem-cell transplantation in multiple myeloma patients: A single-center experience. Egypt J Haematol 2022;47:181-6

How to cite this URL:
Uysal A, Erkurt MA, Kuku &, Kaya E, Berber &, Sarıcı A, Biçim S, Hidayet E, Kaya A, Merter M. The effect of cryopreserved and noncryopreserved stem cells on the outcome of autologous stem-cell transplantation in multiple myeloma patients: A single-center experience. Egypt J Haematol [serial online] 2022 [cited 2023 Mar 30];47:181-6. Available from: http://www.ehj.eg.net/text.asp?2022/47/3/181/366862

Introduction

Multiple myeloma (MM) is a hematologic malignancy characterized by clonal proliferation of plasma cells in the bone marrow. It is the second most common hematologic malignancy and accounts for about 1% of all cancers [1]. High-dose therapy followed by autologous stem-cell transplantation (ASCT) is still the standard practice for treating newly diagnosed MM in fit and young patients. Despite novel antimyeloma agents, including proteasome inhibitors, immunomodulatory drugs, and monoclonal antibodies in combination, the superiority of ASCT remains in terms of both progression-free survival and overall survival [2].

The ASCT process begins with the mobilization of CD34+ stem cells from the bone marrow into the peripheral blood and the collection of CD34+ stem cells. The next process is the administration of high-dose chemotherapy with melphalan, followed by reinfusion of the CD34+ stem cells [3,4]. The CD34+ stem cells are either reinfused fresh (noncryopreserved=non-CP) or cryopreserved (CP) after collection and then infused [5,6]. Dimethyl sulfoxide (DMSO) is commonly used as a cryoprotectant to maintain cell viability, resulting in some adverse reactions such as cardiovascular, neurological, respiratory, renal, and hepatic dysfunction [7]. Moreover, cryopreservation is a costly method and requires additional labor. Therefore, studies have been conducted on the infusion of cells without cryopreservation, showing that this method is safe [8]. Stem cells can remain viable for up to 5 days at 1–4° after collection, which can be applied without freezing after melphalan on day 0 [9,10].

ASCT with non-CP CD34+ stem cells has been performed in our clinic since November 2019. In this study, we presented the experience of our clinic and compared the outcome and safety of ASCT with CP or non-CP CD34+ stem cells in patients with MM.

Patients and methods

This was a single-center retrospective study approved by the local ethics committee and conducted in accordance with the principles of the Declaration of Helsinki. This is a retrospective study. Study data was obtained from patient files. All data were obtained from hospital registers and patients’ clinical records.

Patients

We retrospectively analyzed patients with MM, who underwent ASCT between January 2019 and June 2021. Patients who underwent their first transplant and were administered granulocyte colony-stimulating factor (GCSF) alone or GCSF plus chemotherapy (cyclophosphamide) as the mobilization regimen for transplantation were included in the study. Patients who underwent a tandem transplant or a second transplant due to progression or relapse were excluded. A total of 163 MM patients were enrolled in this study.

Patients’ age at the time of transplantation, sex, M-protein type, disease score at diagnosis, number of treatment lines, treatment protocols, time from diagnosis to transplantation, remission status before transplantation, stem-cell methods (CP or non-CP), the quantity of CD34+ stem cells infused, the conditioning regimen/dose, infusion-related reactions (IRRs), the duration of neutrophil/platelet engraftment, post-transplant infectious complications, transplant-related mortality (TRM) at 30 days, and duration of hospitalization were examined.

Disease score was determined by the International Staging System. Remission status before transplantation was assessed based on the International Myeloma Working Group criteria [11].

Patients were divided into two groups according to the type of stem cells infused to compare relevant variables: the CP group (patients who received cryopreservation cells) and the non-CP group (patients who received noncryopreservation cells).

Mobilization, collection, and storage of cells

GCSF alone was administered at a dose of 10 μg/kg per day as a subcutaneous injection for 4 days. GCSF plus cyclophosphamide was administered at a dose of 4 g/m². Four days after cyclophosphamide administration, CD34+ stem-cell counts at a dose of 10 μg/kg/day were measured by flow cytometry on day 4. If CD34+ cell counts in peripheral blood were more than or equal to 20/μl, stem-cell collection was started; otherwise, GCSF treatment was continued, and on day 5, if CD34+ cell counts in peripheral blood were more than or equal to 10 μl, stem-cell collection by apheresis was started. The collection process was terminated when the minimum target dose of 2 × 10⁶/kg was reached.

Cryopreservation method

Cryopreservation of the collected cells was prepared by adding DMSO at a concentration of 10% and the product was stored in a mechanical freezer at −80°C. The bags were thawed in a 37°C water bath immediately before infusion and the product was reinfused on day 0 after the conditioning regimen.

Noncryopreserved method

The collected CD34+ cells were stored in the blood bag without DMSO at 4°C for up to 72 h. The product was reinfused on day 0 after the conditioning regimen.

Transplantation

Melphalan was used for conditioning regimen in all patients and administered as a single dose on day 2. The dose of 200 mg/m² was administered to the fit and young patients. The dose of 140 mg/m² was administered to fragile patients or patients with a glomerular filtration rate of less than 60 ml/min/1.73 m². Stem cells were infused on day 0. Cell viability and sterility were not routinely tested. All patients received premedication with chlorpheniramine, methylprednisolone, and acetaminophen before stem-cell infusion. GCSF was given on day +1 until neutrophil engraftment.

Duration of neutrophil engraftment was defined as the time from the day of stem-cell infusion to the first of three consecutive days with an absolute neutrophil count more than or equal to 0.5 × 10⁹/l. Duration of platelet engraftment was accepted as the time from the day of stem-cell infusion to the first of three consecutive days with a platelet count greater than 20 × 10⁹/l without transfusion. Febrile neutropenia was considered the combination of granulocyte counts below 500 cells/μl and a temperature above 38°C.

TRM was defined as death within the first 100 days after ASCT without evidence of disease progression. IRRs and complications after cell infusion were recorded. Nausea/vomiting, renal toxicity (acute renal failure), hepatic toxicity (elevated transaminases), and cardiac toxicity (arrhythmia, hypertension/hypotension) after cell infusion were assessed.

The duration of hospitalization after transplantation was calculated as the time from the first day of transplantation to discharge or death from any cause.

Statistical analysis

Numbers with percentages were used for categorical data; χ² tests were performed to determine the association between two and/or more categorical variables. Mean (SD) and median (minimum–maximum) represented parametric continuous variables and nonparametric variables, respectively. The Shapiro–Wilk test, skewness and kurtosis coefficients, and histogram defined parametric and nonparametric continuous variables from the patient data. Student t test (independent t test) was used for parametric variables and Mann–Whitney U test for nonparametric variables. To determine the correlation between quantitative variables, Spearman’s rho test was performed. P value less than 0.05 was considered statistically significant. All data analyses were done using Statistical Package for Social Sciences (SPSS), version 22.0 software: (IBM Corp., Armonk, New York, USA).

Results

A total of 163 patients with MM, who underwent ASCT, were included in this study. Fifty five (33.7%) of them received CP cells, 108 (66.3%) received non-CP cells. In total, 68 (41.7%) of them were female, 95 (58.3%) were male. The mean age of the patients at the time of transplantation was 57.2 ± 9.1 years. The median time from diagnosis to ASCT was 5 (2–18) months in all patients.

The demographic and clinical characteristics of the patients in two groups at the time of transplantation are shown in [Table 1]. At the time of ASCT, there were no significant differences between groups in age (P=0.063) and sex (P=0.391). M-protein subtypes and International Staging System rates were similar in both groups. IGG as heavy chain (CP: 64.75% vs. non-CP: 56%), lambda as light chain (13.7 vs. 18%) were most frequently detected in both groups. There were no statistically significant differences between groups in induction regimens (P>0.999). Bortezomib plus cyclophosphamide plus dexamethasone (VCD) was used most frequently as the induction regimen in both groups (CP: 100% vs. non-CP: 98.1%). Disease status was noted in all patients as complete response in 29.6%, as very good partial response in 56.8%, and as partial response in 13.6%. Disease status was similar in two groups at the time of transplantation, with no statistically significant differences in either group (P=0.103). More than half of patients in both groups had a very good partial response at the time of transplantation (CP: 67.3% vs. non-CP: 51.7%).

Table 1: The demographic and clinical characteristics of the patients at the time of transplantation

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GCSF alone was administered as the mobilization regimen in 145 (89%) patients in the entire cohort. Mobilization regimens differed significantly in the two groups. The use of GCSF plus cyclophosphamide was significantly higher in the CP group than in the non-CP group (25.5 vs. 3.7%, P<0.01). Melphalan was used as a conditioning regimen in all patients, at a dose of 200 mg/kg in 134 (82.2%) patients and at a dose of 140 mg/kg in 29 (17.8%) patients. The melphalan dose was not significantly different between the CP and non-CP groups (P=0.757).

Transplantation characteristics and post-transplantation outcomes are shown in [Table 2]. The median total dose of CD34+ cells was 4.7 × 10⁶/kg (2 × 10⁶–18.4 × 10⁶) in all patients. The median dose of CD34+ cells was similar in both groups, which did not differ significantly [CP: 4.70 (2–18.40)×10⁶ vs. non-CP: 4.80 (2–15.45)×10⁶, P=0.755].

Table 2: The transplantation characteristics and post-transplantation outcomes

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The median duration of neutrophil and platelet engraftment in all patients was 13 (9–22) and 13 (8–25) days, respectively. There was no statistically significant difference in the median duration of neutrophil and platelet engraftment (days) between the CP and non-CP groups [13 (10–22) and 13 (9–19) days vs. 14 (8–25) and 13 (9–21) days, P=0.896 and P=0.183, respectively]. Neutrophil-engraftment failure was detected in two (1.2%) patients and platelet-engraftment failure was detected in three (1.8%) patients in the entire cohort. All these patients were in the non-CP group.

The median duration of hospitalization was 15 (11–31) days after transplantation. No statistical difference in median duration of hospitalization was observed between the CP and non-CP groups [16 (13–26) vs. 15 (11–31) days, P=0.124].

Febrile neutropenia was detected in 83 (50.9%) patients in the entire cohort after transplantation. The febrile neutropenia rate was higher in the CP group than in the non-CP group, but there was no statistical difference between the two groups (CP: 56.4% vs. non-CP: 48.1%, P=0.301).

The rate of use of antibacterial agents, antifungal agents, and antiviral agents was 96.4, 11.7, and 9.2%, respectively, in all patients. The use of antibacterial agents was higher in the CP group (52.7%) than in the non-CP group (47.2%), but not statistically significant (P=0.506). The use of antifungal and antiviral agents was higher in the non-CP group than in the CP group (13.9 vs. 7.3% and 10.2 vs. 7.3%, respectively), but there was no statistically significant difference between the two groups (P=0.324 vs. P=0.748).

Nausea, vomiting, and rash were the most common adverse events, occurring in 15.3% of all patients after infusion. The rates of infusion reactions such as nausea, vomiting, and rash were higher in the CP group than in the non-CP group (21.8 vs. 12%), with no statistically significant difference (P=0.159). The other adverse events such as renal toxicity (acute renal failure), hepatic toxicity (elevated transaminases), and cardiac toxicity (arrhythmia, hypotension/hypertension) after cell infusion were found to be 8, 4.9, and 3.7%, respectively, in all patients. The occurrence of renal and hepatic adverse events was more frequent in the CP group than in the non-CP group (renal: 10.9 vs. 6.5%, hepatic: 5.5 vs. 4.6%).

In the first 100 days, TRM was detected in three (1.8%) of all patients, all of whom were in the non-CP group. The cause of death in all cases was infection in the form of pneumonia. No TRM was detected in the CP group. One hundred and sixty (98.2%) of all patients are still alive.

Discussion

Although new drugs have been added to myeloma treatment in recent years, high-dose therapy followed by ASCT is still the standard practice for fit patients after the induction regimen. ASCT is an effective and safe therapy in patients with MM, whose mortality rate is less than 1% [1,12]. IRRs and infections were the most common adverse events after transplantation for ASCT. One cause of infusion reactions and organ damage is DMSO toxicity. The efficacy and safety of non-CP cells have been demonstrated in studies in which cell viability was maintained for more than 96 h at 4°C in a standard blood-bank refrigerator. Short-term storage at 4° is the recommended method for using cells without cryopreservation. Some retrospective studies have shown that engraftment failure and engraftment rate are similar in CP cells and infusion reactions are lower in CP cells due to the absence of DMSO [13,14].

In this study, we compared the CP and non-CP cells in patients with MM, who underwent ASCT. The demographic and clinical characteristics were similar at the time of transplantation in the CP and non-CP groups. Only the mobilization regimes of the two groups were different before transplantation. This is because GCSF alone has been mainly used as the mobilization regimen in our clinic since January 2019. Non-CP stem cells have also been used since November 2019. In our clinic, the collected CD34+ cells were stored in the blood bag without DMSO for up to 72 h at 4°C in the refrigerator of a blood bank. The product was reinfused on day 0 according to the induction regimen.

The median duration of neutrophil and platelet engraftment was not statistically significantly different in the CP and non-CP groups: 13 (10–22) and 13 (9–19) days versus 14 (8–25) and 13 (9–21) days (P=0.896 and P=0.183, respectively). Neutrophil-engraftment failure was detected in two (1.2%) patients and platelet-engraftment failure was detected in three (1.8%) patients in the entire cohort. All patients were in the non-CP group, who died of infection in the first 30 days. Apart from these three patients, engraftment occurred in all patients in both groups. These results on engraftment duration are consistent with the literature. Jennane etal. [15] studied the non-CP peripheral blood stem cells in 62 patients with MM who had undergone ASCT. In their study, the median neutrophil-engraftment duration was 12 days (range: 7–19), the median platelet-engraftment duration was 14 days (range: 9–32), and the mortality rate within 100 days of transplantation was 3.6%. Some retrospective studies of ASCT with CP cells reported TRM rates of 0–3.2%. In our study, TRM was detected in three (1.8%) of all patients in the first 100 days, all of whom belonged to the non-CP group [6,16].

The present study showed no statistical difference in the median duration of hospitalization between the CP and non-CP groups [16 (13–26) vs. 15 (11–31) days, P=0.124]. Earlier discharge was also achieved when non-CP cells were transplanted. Piriyakhuntorn etal. [17] compared non-CP and CP stem cells for ASCT in MM and found a median duration of hospitalization of 25.5 (18–30) and 33 (17–55) days for non-CP and CP stem cells, respectively.

Sarmiento etal. [18] presented the advantages of non-CP cells over CP cells and emphasized that the rates of febrile neutropenia and mucositis were statistically significantly lower in the non-CP group than in the CP group (40 vs. 92%, P=0.0001 and 11 vs. 64%, P=0.001, respectively). In the same study, the duration of hospitalization was 5 days shorter in the non-CP group (P=0.001). Bittencourt etal. [10] reported that infections and neutropenic fever occurred without statistical difference in the CP group and the non-CP group (41 vs. 29% infections, P=0.23, 41 vs. 38% neutropenic fever, P=0.84, respectively). In our study, the febrile neutropenia rate was higher in the CP group than in the non-CP group, but there was no statistical difference between the two groups (CP: 56.4% vs. non-CP: 48.1%, P=0.301). The use of antibacterial agents was higher in the CP group (52.7%) than in the non-CP group (47.2%), but not statistically significant (P=0.506).

DMSO is the most used cryoprotective agent and causes various types of adverse events such as nausea/vomiting, hypotension/hypertension, diarrhea, flushing, and more severe life-threatening events such as cardiac arrhythmia, encephalopathy, acute renal failure, and respiratory depression [7,19]. Piriyakhuntorn etal. [17] found that infusion reactions in the CP and non-CP groups were 37.5 and 19.2%, respectively. The rate of infusion reactions was high in the CP group but not statistically significant (P=0.72). In our study, the rates of infusion reactions such as nausea, vomiting, and rash were higher in the CP group than in the non-CP group (21.8 vs. 12%), with no statistically significant difference (P=0.159). The renal and hepatic adverse-event rate was higher in the CP group than in the non-CP group (renal: 10.9 vs. 6.5%, hepatic: 5.5 vs. 4.6%).

Conclusions

According to our study results, non-CP cells have a similar outcome to CP cells and lower toxicity than CP cells, which are safe and effective in ASCT. Non-CP stem cells may be preferred to avoid the toxic effects of DMSO and shorten the duration of hospitalization because the adverse events are less.

Acknowledgements

Author contributions: conceptualization: Ayşe Uysal and Mehmet A. Erkurt. Data curation and formal analysis: Ayşe Uysal, Ahmet Sarıcı, Soykan Biçim, Emine Hidayet, Ahmet Kaya, and Mustafa Merter. Investigation and resources: Ayşe Uysal, Ahmet Sarıcı, İlhami Berber, Soykan Biçim, Mustafa Merter, Emin Kaya, and İrfan Kuku. Project administration: Mehmet Ali Erkurt, İlhami Berber, Emin Kaya, and İrfan Kuku. Software: Ayşe Uysal, Soykan Biçim, Emine Hidayet, Ahmet Kaya, and Mustafa Merter. Supervision, validation, and visualization: Mehmet A. Erkurt, Emin Kaya, İrfan Kuku, and İlhami Berber. Writing–review and editing: Ayşe Uysal and Mehmet A. Erkurt.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

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