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Öğe Does Body Mass Index Affect Stem Cell Yield in Healthy Donors?(Cig Media Group, Lp, 2025) Hatipoglu, Ugur; Yilmaz, Seda; Okumus, Nazik; Seyhan, Mert; Seyhan, Rasim; Korkmaz, Gulten; Erkurt, Mehmet Ali[No abstract available]Öğe Does body mass index affect stem cell yield in healthy donors?(Pergamon-Elsevier Science Ltd, 2025) Yilmaz, Seda; Okumus, Nazik; Seyhan, Mert; Sahin, Rasim; Korkmaz, Gulten; Erkurt, Mehmet Ali; Namdaroglu, SinemObjectives: Hematopoietic stem cell transplantation is an important treatment for many benign and malignant diseases. Factors affecting the donor response to mobilization and thus hematopoietic progenitor cell yield have been investigated, but studies on donor body mass index are limited and contradictory. Our aim in our study was to investigate this situation. Material and methods: The data of a total of 665 healthy donors were analyzed and divided into 2 groups as body mass index (BMI) < 25 (group 1, n: 247) and >= 25 kg/m(2) (group 2, n: 418). In addition to demographic data, smoking, blood group, agent used for mobilization, number of days of apheresis, volume of blood processed, amount of product collected, complete blood count before mobilization and biochemical parameters were evaluated. Results: Group 1 consisted of 247 and group 2 consisted of 418 participants. Median age was 29 (18-66) years in group 1 and 37 (18-68) years in group 2. Median BMI was 22.49 (16.10-24.98) and 28.06 (25.00-48.27) kg/m(2), respectively. Male donors constituted 62.7 % in group 1 and 73.9 % in group 2. In group 2, the number of apheresis days was lower and the median CD34(+) stem cell count on the first day and in total was statistically significantly higher (7.1 x10(6)/kg and 7.58 x10(6)/kg, respectively). Conclusion: In healthy donors, CD34(+) stem cells were correlated with BMI, whereas no statistically significant difference was found between the groups in terms of smoking habit, blood group, granulocyte stimulating agent type, processed blood volume, non-lymphocyte and biochemical parameters other than LDH.Öğe Evaluation of the clinical practices and awareness of hematologists related to hepatitis B reactivation(2022) Colkesen, Fatma; Yilmaz, Seda; Duran, MustafaAim: This study aimed to evaluate the awareness and knowledge of hematologists about hepatitis B virus reactivation (HBVr) to draw attention to this subject's importance. Material and Methods: Sixty-six hematologists included in Turkey. A 13-item questionnaire was administered to the study group to evaluate awareness, knowledge, and experience of HBVr. Results: It was thought by 97% of the participants that all patients who were to receive immunosuppressive treatment (IST) should be screened in respect of HBV. While 98.5% of the hematologists thought HBsAg should be examined in the screening, 89.4% thought anti-HBcIgG should be examined. A total of 89.4% of the hematologists stated that prophylaxis should be started before IST. HBV prophylaxis had been previously administered to patients receiving IST by 97% of the hematologists, and 44% had encountered HBVr at least once in patients. Training related to HBVr after IST had been received following graduation by 75.8% of the hematologists. Conclusions: Awareness about HBVr was found to be high in the hematologists in this study. However, it is worrying that there are clinicians not using anti-HBcIgG test in screening, and the screening rate before treatment with tyrosine kinase inhibitors was low. There was seen to be no standard follow-up protocol either for patients who had started or had not started prophylaxis. This study can be considered to be a stimulus on the subjects of preventing patients with isolated anti-HBcIgG positivity being overlooked, determining the HBVr risk associated with IST, and optimizing the follow-up of patients.Öğe Fresh and cryopreserved stem cell transplantation in myeloma patients: Does it make a difference on transplant outcomes?(Pergamon-Elsevier Science Ltd, 2025) Erkurt, Mehmet Ali; Yilmaz, Seda; Namdaroglu, Sinem; Demircioglu, Sinan; Sarici, Ahmet; Cirik, Salih; Koroglu, MustafaObjective: The standard approach for multiple myeloma patients eligible for transplantation includes 4-6 cycles of induction therapy, followed by autologous stem cell transplantation (aHSCT). The aHSCT process starts with stem cell mobilization and collection, followed by high-dose chemotherapy and reinfusion of the harvested stem cells. These cells can be infused fresh within 24-48 h post-collection or cryopreserved for future use. Herein we analyzed the outcomes of aHSCT patients receiving infusions of fresh versus cryopreserved hematopoietic stem cells. Materials and methods: This multicenter retrospective study analyzed 88 adult patients diagnosed with multiple myeloma who underwent aHSCT (n = 43 for cryopreserved; n = 45 for fresh infused group). Results: A total of 88 patients were included in the study. 39.7 % of patients were female and 60.3 % of patients were male. No correlation was observed between pre-mobilization disease status, mobilization regimen, and disease risk status as defined by the R-ISS system (p = 0.1, p = 0.8). The median neutrophil engraftment time was 10 days in the fresh group and 12 days in the cryopreserved group (p < 0.01). In contrast, the median platelet engraftment time was 12 days in the fresh group and 11 days in the cryopreserved group (p < 0.01). Engraftment was achieved in all patients included in the study. Conclusion: The shorter neutrophil engraftment time in the fresh group and the shorter platelet engraftment time in the cryopreserved group, along with successful engraftment in all patients, suggest that both options are reasonable within the MM aHSCT protocol.Öğe Is there a relationship between stem cell yield obtained from healthy donors and healthy donors' blood type?(Pergamon-Elsevier Science Ltd, 2025) Katircilar, Yavuz; Sahin, Abdulkadir; Aydin, Muruvvet Seda; Erer, Kerim; Erkurt, Mehmet Ali; Namdaroglu, Sinem; Yilmaz, SedaBackground and objectives: Factors affecting adequate mobilization and apheresis are critical for a good yield of hematopoietic stem cells (HSCs) in the final product. A female donor, advanced age, smoking, high lactate dehydrogenase levels, high absolute lymphocyte count at baseline were found to be inversely correlated to the number of harvested CD34+ cells. However, the data on whether there is a correlation between blood types A, B, AB, O and the number of harvested CD34+ cells is insufficient. The aim of this study is to investigate the effect of blood types on the stem cell yield in healthy donors. Material and methods: A total of 807 healthy donors from 10 centers in T & uuml;rkiye were included in this retrospective study. Donors were subdivided into four groups as A, B, AB, O by their blood types. These four groups were compared in terms of age, sex, ECOG performance score, smoking status, and the amount of harvested CD34+ stem cells. Results: The median age of the 807 healthy donors included in the study was 35 years (11-70). 256 (31.7 %) donors were female and 551 (68.2 %) donors were male. There were 349 donors in type A blood group, 134 in type B blood group, 53 in type AB blood group and 271 donors in type O blood group. The median amount of CD34+ cells in the total apheresis product was 7.67 x 106 per kg in type O blood group, 7.52 x 106 per kg in type A blood group, 7.2 x 106 per kg in type B blood group, and 7.45 x 106 per kg in type AB blood group. There was no statistically significant difference among the groups (p:0.673). Smoking was lower in the type B blood group with 29.1 % compared to the other groups. However, there was no statistically significant difference in total amount of CD34+ stem cells in the type B blood group who smoked less (p = 0.949). Conclusion: In our study in which we have retrospectively analyzed the effect of donor blood types on the efficiency of HSCs harvested from peripheral blood in healthy donors, no correlation was found between the blood types and the mobilization and amount of harvested CD34+ cells.Öğe Is there a relationship between vitamin D levels and graft versus host disease?(Pergamon-Elsevier Science Ltd, 2025) Yigenoglu, Tugce Nur; Ulu, Bahar Uncu; Namdaroglu, Sinem; Erkurt, Mehmet Ali; Sahin, Rasim; Okumus, Nazik; Yilmaz, SedaObjective: Vitamin D deficiency is common in adult patients undergoing allogenic hematopoietic stem cell transplantation (allo-HSCT). Since vitamin D is an important regulatory factor for the immune system, vitamin D deficiency may have effects on antitumor activity, relapse rates, graft versus host disease (GVHD) occurrence and infection rates in allo-HSCT. We aimed to investigate the effects of vitamin D levels on the outcome of allo-HSCT. Material and methods: This study included 211 patients who underwent allo-HSCT at seven transplant centers in T & uuml;rkiye. The impact of pretransplant vitamin D level on overall survival (OS), relapse rate, GVHD occurrence and engraftment times was analyzed retrospectively Results: Pretransplant vitamin D levels were not related to the neutrophil engraftment day (p: 0.887), relapse rate (p: 0.433) and GVHD occurrence (p: 0.391). At a median follow-up of 14 months, OS was 84.8 % and median OS was not reached. Univariate Cox Regression analysis showed that higher levels of vitamin D (>12 ng/mL) affected the survival rates (p = 0.029) (HR: 0.392: 95 % CI: 10.170-0.907). Conclusion: In our study, pretransplant vitamin D levels were not related to GVHD occurrence, relapse rate and engraftment times. However, we found that higher levels of pretransplant vitamin D levels (threshold is 12 ng/ mL) were associated with increased survival. Further studies with a larger population are necessary to reveal the role of vitamin D in patients undergoing allo-HSCT.Öğe The comparison of cyclophosphamide at different dose levels for stem cell mobilization in multiple myeloma(Pergamon-Elsevier Science Ltd, 2025) Karakus, Abdullah; Hatipoglu, Ugur; Katircilar, Yavuz; Erkurt, Mehmet Ali; Yilmaz, Seda; Cagliyan, Gulsum Akgun; Ozturk, FahirBackground: We conducted a multi-center retrospective non-randomized study to clarify roles of 2 and 3 gr/m2 doses of Cyclophosphamide (Cy) for stem cell mobilization in Multiple Myeloma. Material and methods: This study analyzed 169 adult patients who received Cy-based mobilization regimen at doses 2 and 3 gr/m2 between 2018 and 2024. All patients included in this study were 18 years old and older. Patients divided into two groups; group 1 represents 2 gr/m2 treated patients, and group 2 represents 3 gr/m2 dosing. These two groups then compared in terms of CD34+ cell number collected by apheresis, apheresis days, peak peripheral blood CD34+ value and rates of mobilization failures. Results: Higher doses of Cy yielded more hematopoietic stem cells compared to the lower dose Cy [10.00 (3.00-28.90) vs 9.01 (5.00-14.90), p = 0.002]; while mobilization failures and apheresis days were comparable across groups (p = 0.112 and p = 0.648, respectively). Apheresis days required for adequate stem cell harvest among groups was found statistically similar (p = 0.648). Conclusion: This study indicated the superior efficacy of 3 gr/m2 dose of Cy in terms of stem cell yield. However, mobilization failure and prolonged apheresis sessions were not issues with lower doses.Öğe The effect of threosulfan-based versus busulfan-based preparation regimens on transplant outcomes(Pergamon-Elsevier Science Ltd, 2025) Candir, Burcu Aslan; Okumus, Nazik; Hindilerden, Ipek Yonal; Erkurt, Mehmet Ali; Namdaroglu, Sinem; Merter, Mustafa; Yilmaz, SedaBackground: Allogeneic hematopoietic stem cell transplantation is a curative therapy for malignant and nonmalignant hematologic disorders. Conditioning regimens, such as those based on busulfan, are utilized to promote engraftment. Busulfan-based regimens are commonly employed but exhibit significant toxicity, leading to interest in alternate drugs such as treosulfan, which may offer a superior safety profile while preserving efficacy. Methods: This retrospective study examined 240 adult patients diagnosed with acute myeloid leukemia or acute lymphoblastic leukemia who received allogeneic hematopoietic stem cell transplantation at nine transplantation centers in T & uuml;rkiye from 2010 to 2024. Patients underwent either a busulfan-based or treosulfan-based conditioning regimen. Results: Engraftment was effective in both groups, with neutrophil engraftment happening earlier in the busulfan group (13 days vs. 15 days, p = 0.001). The incidence of veno-occlusive disease was significantly higher in the busulfan group (10.1 % vs. 0.9 %, p = 0.002). Cytomegalovirus infections were more prevalent in the busulfan group (51.2 % vs. 26.1 %, p < 0.001). Acute graft versus host disease occurred more frequently in the busulfan group (27.9 % vs. 18.9 %, p = 0.128); nonetheless, this difference did not reach statistical significance. No significant differences in relapse rates were detected through the groups. The overall survival was not reached in the busulfan group, while the treosulfan group demonstrated an overall survival of 40 months. Conclusion: Treosulfan-based conditioning regimens demonstrate similar efficacy to busulfan-based regimens while presenting a more acceptable toxicity profile. Treosulfan-based regimens also show a lower occurrence of veno-occlusive disease and cytomegalovirus infections.Öğe The role of heparin in autologous stem cell mobilization in patients with multiple myeloma(Pergamon-Elsevier Science Ltd, 2025) Sarici, Ahmet; Erkurt, Mehmet Ali; Yilmaz, Seda; Demircioglu, Sinan; Berber, Ilhami; Basturk, Abdulkadir; Merter, MustafaBackground : Autologous hematopoietic stem cell transplantation (aHSCT) has become the standard treatment modality for eligible multiple myeloma (MM) patients. One of the most important parameters affecting the success of transplantation is the number of CD34(+) stem cells collected. The most commonly used agents to facilitate the release of CD34(+) stem cells into peripheral blood are granulocyte colony-stimulating factor and plerixafor. Heparin has also been shown to enhance the release of CD34(+) stem cells into peripheral blood. We aimed to report the effect of heparin on the number of CD34(+) stem cells in peripheral blood in MM patients who underwent aHSCT. Materials and methods : This multicenter retrospective study analyzed 138 adult patients diagnosed with MM who underwent aHSCT. Patients were divided into two groups: those who received heparin (n = 108) and those who did not receive heparin before aHSCT (n = 30). Results : The complete response, partial response, and very good partial response rates in the heparin group were 17 % (n = 18), 24 % (n = 26), and 59 % (n = 64), respectively. In the non-heparin group, 20 % of patients (n = 6) achieved complete response, while partial response and very good partial response rates were 33 % (n = 10) and 47 % (n = 14), respectively. There was no statistically significant difference between the groups regarding obesity, ECOG performance scores, and smoking status (p = 0.399, 0.578, and 0.602, respectively). The number of collected CD34(+) stem cells and the peak CD34(+) stem cell count in peripheral blood were significantly higher in the heparin group compared to the control group (both p < 0.001). Conclusion : Heparin has been shown to enhance the migration of CD34(+) stem cells into peripheral blood and facilitate the peripheral stem cell collection process.
