Outcome of Hematopoietic Stem Cell Transplantation in 813 Pediatric Patients with Fanconi Anemia.

Allogeneic hematopoietic stem cell transplantation (HSCT) is the only established curative option for Fanconi anemia (FA) associated bone marrow failure (BMF)/aplastic anemia (AA) and hematological malignancy. We performed a retrospective multicenter study on 813 FA children undergoing first HSCT between 2010 and 2018. Median duration of follow-up was 3.7 years (interquartile range, 3.4-4.0). Median age at transplant was 8.8 years (6.5-18.1). Overall survival (OS), event-free survival (EFS) and GvHD-free, relapse-free survival (GRFS) at 5 years were 83% (80-86%), 78% (75-81%) and 70% (67-74%) respectively. OS was comparable between matched family donor (MFD, n=441, 88%) and matched unrelated donor (MUD, n=162, 86%) and was superior to that of mismatched family or unrelated donor (MMFD/MMUD, n=144, 72%) and haploidentical donor (HID) (n=66, 70%, p<0.001). In multivariable analysis, a transplant indication of acute myeloid leukaemia/myelodysplastic syndrome compared to AA/BMF, use of MMFD/MMUD and HID compared to MFD, Fludarabine-Cyclophosphamide (FluCy) + other conditioning compared to FluCy independently predicted inferior OS, while alemtuzumab compared to ATG was associated with better OS. Age  10 years was associated with worse EFS and GRFS. Cumulative incidences (CIN) of primary and secondary graft failure were 2% (1-3%) and 3% (2-4%) respectively. CIN of grade II-IV acute GvHD, grade III-IV acute GvHD and chronic GvHD were 23% (20-26%), 12% (10-15%) and 8% (6-10%) respectively. The 5-year CIN of secondary malignancy was 2% (1-3%). These data suggest that HSCT should be offered to Fanconi Anemia patients with AA/BMF at a younger age in the presence of a well-matched donor.

Retrospective Evaluation of Relationship Between Iron Overload and Transplantation Complications in Pediatric Patient Who Underwent Allogeneic Stem Cell Transplantation Due to Acute Leukemia and Myelodysplastic Syndrome.

BACKGROUND: Hematopoietic stem cell transplantation (HSCT) is a curative therapy option for hematologic malignancies. Iron overload is common in this patient group and can impact short-term and long-term nonrelapse mortality. STUDY DESIGN: Retrospective observational cohort study. AIMS: To evaluate the effect of iron load on early and late HSCT outcomes in patients with acute leukemia and myelodysplasia to assess the necessity of reducing iron load. PATIENTS AND METHODS: Sixty patients who underwent HSCT in pediatric stem cell transplantation unit between 2000 and 2012 were evaluated retrospectively. The patients were divided into those with pretransplantation serum ferritin levels above and below the median value of 1299 ng/mL. RESULTS: Forty-two (70%) of the patients were male, mean ages of the low and high ferritin groups were 85.43±9.42 and 118.56±10.04 months, respectively. Acute graft-versus-host disease (GVHD) within the first 100 days and acute liver GVHD were significantly more common in the high ferritin group (P<0.011 for both). Ferritin level was not associated with rates of engraftment syndrome, veno-occlusive disease, early/late infection, relapse, or overall and disease-free survival. CONCLUSIONS: In our study, significant result especially in terms of acute liver GVHD, was important to emphasize the need to be more careful in terms of acute liver GVHD risk in early liver pathologies in patients with high levels of ferritin after transplantation. In future large studies may be helpful to explain the relationship between acute liver GVHD and high ferritin levels.

Hematopoietic Stem Cell Transplantation in Patients with Hemoglobinopathies.

Hemoglobinopathies are the most common single-gene diseases and are estimated to affect millions of people worldwide. Thalassemia and sickle cell disease are the most prevalent diseases of this group. Today, despite the decreasing number of newborns diagnosed with a hemoglobinopathy, it remains an important health problem for many countries. Although regular red blood cell (RBC) transfusions, advanced iron chelation, and supportive therapy alternatives have improved life expectancy, allogeneic hematopoietic stem cell transplantation (HSCT) is the only curative option for patients with hemoglobinopathies to prevent irreversible organ damage. Modern transplantation approaches and careful posttransplantation follow-up of patients have improved survival outcomes, and HSCT has now been performed in several patients with hemoglobinopathies worldwide. Considering current experiences, hematopoietic stem cell transplantation is recommended in cases of ß-thalassemia (ß-thal) in the presence of a matched family or unrelated donor, without secondary organ damage due to transfusion. In patients with sickle cell anemia, transplantation indications include transfusion dependence and cases of secondary organ damage. Recently, gene therapy as a possible treatment option has yielded promising results, though it is not in routine clinical use at its current stage.

Haploidentical hematopoietic stem cell transplantation with post-transplant high-dose cyclophosphamide in high-risk children: A single-center study.

Recently, haploidentical transplantations have been performed with unmanipulated BM or PBSC. This approach is becoming more widely adopted with the use of PTCY. However, there is limited evidence about this approach in children. We present 15 children who received 16 haploidentical HSCT with unmanipulated BM or PBSC using PTCY for GVHD prophylaxis. Post-transplant CY(50 mg/kg IV) was given on the third and fifth day, and CsA or tacrolimus with MMF or MP was also used for GVHD prophylaxis. All patients engrafted at a median of 16 and 18 days for neutrophil and thrombocyte recovery, respectively. Grades II-III acute GVHD developed in seven patients, and mild chronic GVHD was found in two patients. Two patients died within the first 100 days due to sepsis (TRM 12.5%). Eleven patients are currently alive, with a median follow-up of 12 months (range 6-22 months). The 12-month OS and DFS were 75 ± 10.8% and 68.8 ± 11.6%, respectively. Our results with these high-risk patients are encouraging for haploidentical HSCT in pediatric patients. Future studies should continue to assess haploidentical HSCT, including comparison of other modalities, in a primary pediatric population.

New autoimmune diseases after cord blood transplantation: a retrospective study of EUROCORD and the Autoimmune Disease Working Party of the European Group for Blood and Marrow Transplantation.

To describe the incidence, risk factors, and treatment of autoimmune diseases (ADs) occurring after cord blood transplantation (CBT), we analyzed both CBT recipients reported to EUROCORD who had developed at least 1 new AD and those who had not. Fifty-two of 726 reported patients developed at least 1 AD within 212 days (range, 27-4267) after CBT. Cumulative incidence of ADs after CBT was 5.0% +/- 1% at 1 year and 6.6% +/- 1% at 5 years. Patients developing ADs were younger and had more nonmalignant diseases (P < .001). ADs target hematopoietic (autoimmune hemolytic anemia, n = 20; Evans syndrome, n = 9; autoimmune thrombocytopenia, n = 11; and immune neutropenia, n = 1) and other tissues (thyroiditis, n = 3; psoriasis, n = 2; Graves disease, n 1; membranous glomerulonephritis, n = 2; rheumatoid arthritis, n = 1; ulcerative colitis, n = 1; and systemic lupus erythematosus, n = 1). Four patients developed 2 ADs (3 cases of immune thrombocytopenia followed by autoimmune hemolytic anemia and 1 Evans syndrome with rheumatoid arthritis). By multivariate analysis, the main risk factor for developing an AD was nonmalignant disease as an indication for CBT (P = .0001). Hematologic ADs were most often treated with steroids, rituximab, and cyclosporine. With a median follow-up of 26 months (range, 2-91), 6 of 52 patients died as a consequence of ADs. We conclude that CBT may be followed by potentially life-threatening, mainly hematologic ADs.

Risk of complications during hematopoietic stem cell collection in pediatric sibling donors: a prospective European Group for Blood and Marrow Transplantation Pediatric Diseases Working Party study.

We investigated prospectively factors influencing the safety of hematopoietic stem cell (HSC) collection in 453 pediatric donors. The children in the study donated either BM or peripheral blood stem cells (PBSCs) according to center policy. A large variability in approach to donor issues was observed between the participating centers. Significant differences were observed between BM and PBSC donors regarding pain, blood allotransfusion, duration of hospital stay, and iron supplementation; however, differences between the groups undergoing BM vs PBSC donation preclude direct risk comparisons between the 2 procedures. The most common adverse event was pain, reported mainly by older children after BM harvest, but also observed after central venous catheter (CVC) placement for PBSC collection. With regard to severe adverse events, one patient (0.7%) developed a pneumothorax with hydrothorax after CVC placement for PBSC collection. The risk of allotransfusion after BM harvest was associated with a donor age of < 4 years and a BM harvest volume of > 20 mL/kg. Children < 4 years were at higher risk than older children for allotransfusion after BM harvest and there was a higher risk of complications from CVC placement before apheresis. We conclude that PBSC and BM collection are safe procedures in children.

Deviating from safety guidelines during deferiprone therapy in clinical practice may not be associated with higher risk of agranulocytosis.

BACKGROUND: A risk associated with the iron chelator deferiprone is the development of neutropenia or agranulocytosis. Accordingly, the product label recommends weekly blood monitoring and immediate interruption of treatment upon detection of an absolute neutrophil count (ANC) <1.5 × 10(9)/L, out of concern that continued therapy might lead to a more severe drop. However, it is uncertain how these recommendations are followed under real-life conditions and, if they are not followed, whether continuation of therapy results in increased incidence of agranulocytosis. PROCEDURE: This non-interventional surveillance program assessed the monitoring of deferiprone therapy in clinical practice. A total of 294 patients with transfusion-dependent anemias received deferiprone, as monotherapy or with another chelator, for up to 1 year. The participating physicians were not given any instructions about treatment and monitoring beyond being referred to the information in the package insert. RESULTS: ANC monitoring was conducted at an average interval of 5 ± 4 weeks, and deferiprone was not always interrupted upon detection of neutropenia. One patient (0.3%) experienced agranulocytosis, and nine others (3%) experienced a total of 11 episodes of neutropenia. All neutropenia episodes resolved; median time to resolution was similar whether or not treatment was interrupted; and no case of neutropenia progressed to agranulocytosis. CONCLUSIONS: These data indicate that less frequent ANC monitoring and continuation of deferiprone therapy during neutropenia are not associated with prolonged neutropenia or with progression to agranulocytosis.

Newborn screening for sickle cell anemia in Antalya, Türkiye.

BACKGROUND: In a screening study conducted on adults, the prevalence of sickle cell traits in Antalya was found to be 0.24%. Since no screening studies have been conducted in the neonatal period in our region, the exact incidence has not been determined. In this study, we aim to report our experience of neonatal screening for sickle cell disease in Antalya, Türkiye. METHODS: During a 14-month period, 2562 heel prick blood samples, taken on filter paper from Akdeniz University Hospital, Antalya Education and Research Hospital and Antalya Atatürk State Hospital and four other healthcare centers, were studied using the high pressure liquid chromatography method. Blood samples were studied using the `Sickle Cell Short Program` test method on a Bio Rad Variant device. RESULTS: In the study, no patients with sickle cell disease were identified. Four newborns who were sickle cell carriers (0.15%) and two newborns who were Hemoglobin D carriers (0.08 %), were found. CONCLUSION: Considering the efficiency and cost calculations made as a result of the data obtained from our study, it was concluded that sickle cell screening would not be effective in newborns. It seems more effective and economical to screen the children of parents, who are found to be at risk for Hemoglobin S carriage as a result of premarital tests.

The value of donor lymphocyte infusions in thalassemia patients at imminent risk of graft rejection following stem cell transplantation.

BACKGROUND: The aim was to evaluate the feasibility of donor lymphocyte infusion (DLI) in transplanted patients with thalassemia who were at imminent risk of graft rejection (GR). PROCEDURE: We retrospectively evaluated outcomes in a cohort of 19 patients with thalassemia who received DLI following 21 transplantations. Patients were divided into three groups depending on indication and time of DLI: group I, mixed chimerism-level-3 (MC-level-3) within 2 months and subsequently receiving DLI; group II, MC-level-3 within 2 months and receiving deferred DLI beyond post-transplant 2.5 months; group III, receiving DLI because of a gradual decrease in both donor cells and hemoglobin levels without MC-level-3 within 2 months. RESULTS: Three patients evolved to compete chimerism (16%), 9 patients had MC with transfusion independency (47%) and 7 had GR (37%). Three of 7 patients in group I, 1 of 4 patients in group II and 8 of 10 patients in group III preserved the graft. Although significant increases in the percentage of donor cells were not detected in group III, hemoglobin levels improved (median, 6.8-8.8 g/dl, P = 0.002). CONCLUSION: The risk of GR is high in patients with thalassemia who have MC-level-3 within 2 months after transplantation. DLI is a feasible method for converting unstable MC towards stable MC or full donor chimerism, but its efficacy is partially related to the percentage of residual host cells at the time of infusion. Serial chimerism studies can identify unstable MC earlier and may guide the proper timing of intervention.

HLA-matched family hematopoetic stem cell transplantation in children with beta thalassemia major: the experience of the Turkish Pediatric Bone Marrow Transplantation Group.

From January 1991 to June 2009, 245 children with beta thalassemia major who underwent their first allogeneic HSCT in Turkey and who were followed for a minimum of one yr post-transplantation were enrolled this study. The median age of the patients was 6.6 yr old (range, 1-22 yr). The distribution of Pesaro risk class I, II, and III categories was 41, 130, and 63 children, respectively. The median serum ferritin level was 2203 ng/mL. Eighty-eight patients received bone marrow (BM) stem cells; 137, peripheral blood (PB) stem cells; and 20, cord blood (CB) stem cells. The donors were HLA-matched siblings or parents. Median engraftment times were shorter in PBSCT patients compared with the BMT group (p < 0.001). Grade II-IV acute GvHD was observed in 33 children (13.5%), while cGvHD was observed in 28 patients (12.5%), eight of whom had the extensive form. Thalassemic reconstitution was observed in 43 (17%) of the transplant patients. Post-transplant aplasia occurred in three patients, and the TRM rate was 7.75%. Seventeen patients were lost after 100 days. The thalassemia-free survival and OS rates were 68% (95% CI, 61.8-74.2) and 85.0% (95% CI, 80.2-89.8), respectively. We believe that this study is important because it is the first multicenter national data for children with beta thalassemia major receiving HSCT.

Thalassemia-free and graft-versus-host-free survival: outcomes of hematopoietic stem cell transplantation for thalassemia major, Turkish experience.

We report the national data on the outcomes of hematopoietic stem cell transplantation (HSCT) for thalassemia major (TM) patients in Turkey on behalf of the Turkish Pediatric Stem Cell Transplantation Group. We retrospectively enrolled 1469 patients with TM who underwent their first HSCT between 1988 and 2020 in 25 pediatric centers in Turkey. The median follow-up duration and transplant ages were 62 months and 7 years, respectively; 113 patients had chronic graft versus host disease (cGVHD) and the cGVHD rate was 8.3% in surviving patients. Upon the last visit, 30 patients still had cGvHD (2.2%). The 5-year overall survival (OS), thalassemia-free survival (TFS) and thalassemia-GVHD-free survival (TGFS) rates were 92.3%, 82.1%, and 80.8%, respectively. cGVHD incidence was significantly lower in the mixed chimerism (MC) group compared to the complete chimerism (CC) group (p < 0.001). In survival analysis, OS, TFS, and TGFS rates were significantly higher for transplants after 2010. TFS and TGFS rates were better for patients under 7 years and at centers that had performed over 100 thalassemia transplants. Transplants from matched unrelated donors had significantly higher TFS rates. We recommend HSCT before 7 years old in thalassemia patients who have a matched donor for improved outcomes.

Posttransplant oral iron-chelating therapy in patients with beta-thalassemia major.

Allogeneic hematopoetic stem cell transplantation (HSCT) is the only radical cure of beta-thalassemia. However, iron overload remains a cause of morbidity and mortality in posttransplant period. The authors present 7 patients as a preliminary report who underwent bone marrow transplant (BMT) and received oral chelating therapy (deferasirox) because of poor compliance to phlebotomy and desferrioxamine. The patients investigated mainly for possible side effects of deferasirox. No negative effect was seen in aspartate aminotransferase (AST), alanine aminotransferase (ALT), hemoglobin (Hb), and donor chimerism of the patients while serum ferritin levels significantly reduced (P = .018). Although serum creatinin significantly increased (P = .034), it was in normal limits in all patients. The authors believe that this report shows promising findings to plan further studies to clarify clinical safety and efficacy of deferasirox in posttransplant period.

Cidofovir for BK virus-associated hemorrhagic cystitis: a retrospective study.

BACKGROUND: BK virus-associated hemorrhagic cystitis (BKV-HC) is a severe complication after allogeneic hematopoietic stem cell transplantation (HSCT), but antiviral treatment for this condition has not been evaluated. METHODS: We conducted a retrospective survey on the safety and outcome of cidofovir treatment for patients with BKV-HC in centers affiliated with the European Group for Blood and Marrow Transplantation. RESULTS: From 1 April 2004 to 31 December 2007, 62 patients received a diagnosis of BKV-HC after a median interval of 35 days after HSCT (range, 3-577 days). Fifty-seven patients (92%) received intravenous cidofovir, whereas 5 patients received cidofovir intravesically. Complete response (CR) was recorded in 38 (67%) of 57 patients with HC treated with intravenous cidofovir, whereas partial response (PR) was documented in 7 patients (12%). CR was documented in 3 patients and PR in 1 patient with HC treated with intravesical cidofovir. A reduction of 1-3 logs in BKV load was documented in 8 of the 10 patients achieving CR. Mild-to-moderate toxic effects were recorded in 18 of 57 patients who received intravenous cidofovir administration. In a multivariate analysis, the factors significantly associated with response to cidofovir were the stem cell source (P = .01) and the use of total body irradiation (P = .03). After a median follow-up of 287 days, overall survival and total treatment-related mortality rates were 63% and 40% for patients achieving CR, compared with 14% and 72% for patients with PR or no response to cidofovir, respectively (P = .001 and P = .001, respectively). CONCLUSIONS: Cidofovir may be a potentially effective therapy for BKV-HC, but evidence supporting its use requires randomized controlled trials.

Unrelated cord blood transplantation in children with severe congenital neutropenia.

SCN is an inherited hematological disorder with severe neutropenia and recurrent infections. Although there are some reports that recombinant rhG-CSF improves clinical outcome, allogeneic HSCT appears to be the only curative treatment for these patients. We report here two children with SCN successfully treated by CBT from unrelated donors. They were refractory to rhG-CSF treatment and have no identical family donor. Bu + CY were given as conditioning. Case 1 and Case 2 received 6/6 and 5/6 HLA-matched unrelated umbilical cord blood, respectively. The number of infused nucleated cells was 6, 18 x 10(7)/kg and CD34(+) cell number was 3, 74 x 10(5)/kg in Case 1. Those cell numbers were 8, 8 x 10(7)/kg and 5, 34 x 10(5)/kg for Case 2, respectively. Neutrophil/platelet engraftments were 45/49 days in Case 1 and 24/36 days in Case 2. Grade II cutaneous acute GVHD was seen in Case 2 that was treated successfully with prednisolone. Both patients are well with normal hematological findings and full donor chimerism for post-transplant 20 and 24 months, respectively. We conclude that UCB can be considered as a safe source of stem cell in patients with SCN who need urgent HSCT.

Gap-PCR Screening for Common Large Deletional Mutations of ß-Globin Gene Cluster Revealed a Higher Prevalence of the Turkish Inversion/Deletion (δß)0 Mutation in Antalya.

OBJECTIVE: Although the calculated carrier frequency for point mutations of the ß-globin gene is around 10% for Antalya Province, nothing is known about the profile of large deletional mutations involving the ß-globin gene. In this study, we aimed to screen common deletional mutations in the ß-globin gene cluster in patients for whom direct DNA sequencing was not able to demonstrate the mutation(s) responsible for the disease phenotype. MATERIALS AND METHODS: Thirty-one index cases selected with a series of selection events among 60 cases without detected ß-globin gene mutation from 580 thalassemia-related cases tested by direct sequencing over the last 4 years in our diagnostic center were screened for the most common 8 different large deletional mutations of the ß-globin gene cluster by gap-PCR. RESULTS: We detected 1 homozygous and 9 heterozygous novel unrelated cases for the Turkish inversion/deletion (δß)0 mutation in our series of 31 cases. Our study showed that the Turkish inversion/deletion (δß)0 mutation per se accounts for 16.6% of the unidentified causative alleles and also accounts for 1.5% of all detected mutations over the last 4 years in our laboratory. CONCLUSION: Since molecular diagnosis of deletional mutations in the ß-globin gene cluster warrants different approaches, it deserves special attention in order to provide prenatal diagnosis and prevention opportunities to the families involved. We conclude that the Turkish inversion/deletion (δß)0, as the most prevalent deletional mutation detected so far, has to be routinely tested for in Antalya, and the gap-PCR approach has valuable diagnostic potential in the patients at risk.

Prognostic Factors and a New Prognostic Index Model for Children and Adolescents with Hodgkin's Lymphoma Who Underwent Autologous Hematopoietic Stem Cell Transplantation: A Multicenter Study of the Turkish Pediatric Bone Marrow Transplantation Study Group.

OBJECTIVE: The prognostic factors and a new childhood prognostic index after autologous hematopoietic stem cell transplantation (AHSCT) in patients with relapsed/refractory Hodgkin's lymphoma (HL) were evaluated. MATERIALS AND METHODS: The prognostic factors of 61 patients who underwent AHSCT between January 1990 and December 2014 were evaluated. In addition, the Age-Adjusted International Prognostic Index and the Childhood International Prognostic Index (CIPI) were evaluated for their impact on prognosis. RESULTS: The median age of the 61 patients was 14.8 years (minimum-maximum: 5-20 years) at the time of AHSCT. There were single relapses in 28 patients, ≥2 relapses in eight patients, and refractory disease in 25 patients. The chemosensitivity/chemorefractory ratio was 36/25. No pretransplant radiotherapy, no remission at the time of transplantation, posttransplant white blood cell count over 10x103/µL, posttransplant positron emission tomography positivity at day 100, and serum albumin of <2.5 g/dL at diagnosis were correlated with progression-free survival. No remission at the time of transplantation, bone marrow positivity at diagnosis, and relapse after AHSCT were significant parameters for overall survival. CONCLUSION: The major factors affecting the progression-free and overall survival were clearly demonstrated. A CIPI that uses a lactate dehydrogenase level of 500 IU/L worked well for estimating the prognosis. We recommend AHSCT at first complete remission for relapsed cases, and it should also be taken into consideration for patients with high prognostic scores at diagnosis.

Stem cell transplantation in hemoglobinopathies.

beta-Thalassemia (thal) and sickle cell disease are the most common genetic diseases worldwide. Although supportive therapies such as regular transfusion and chelation for beta-thal and hydroxyurea (HU) for sickle cell disease have significantly improved clinical manifestations and the quality of life, they cannot eliminate disease and therapy-related complications. Today, hematopoietic stem cell transplantation (HSCT) is the only curative treatment for patients with hemoglobinopathies. The first successful HSCT was reported in 1981. At that time, more than 1,000 patients underwent HSCT in Pesaro, Italy. Sixty beta-thal patients underwent HSCT at the Department of Pediatric Hematology-Oncology, Akdeniz University School of Medicine, Antalya, Turkey between 1998 and 2006. We found stable mixed chimerism in 14 patients out of 45 (31%) in our transplanted thalassemia patients. The thalassemia free survival and overall survival rates were found to be 84.0 and 91.0%, respectively. The literature and our results indicate that HSCT can offer a cure for hemoglobinopathy patients.