Improvement of survival after hematopoietic stem cell transplantation and trends at a pediatric transplantation center; a three-decade journey.

BACKGROUND: Advances in stem cell transplantation have resulted in improved outcomes. METHODS: This is a retrospective study aimed to analyze changes in patient profile, transplantation, graft characteristics, and outcome among 241 pediatric patients who received stem cell transplantation in a single center between 1993 and 2019. RESULTS: In the 2010-2019, compared with the 1993-2009 period, a significantly higher 5-year overall survival (60% vs. 44%, p = .022) and an event-free survival (53% vs. 34%, p = .025) were observed. Cumulative incidence of deaths due to relapse or progression between the 1993-2009 and 2010-2019 periods were 33% and 26% respectively (p = .66). Cumulative incidence of non-relapse mortality was significantly higher during the 1993-2009 period compared with the 2010-2019 period for malignant diseases (57.7% vs. 28.3%, p = .007). The overall survival from acute graft-versus-host disease between 1993 and 2009 was 11% versus 46% between 2010 and 2019 (p = .0001). The overall survival from infection in both eras did not show any difference (p = .41). CONCLUSIONS: Development in transplantation technology has led to a decrease in non-relapse mortality and better control of graft-versus-host disease. However, relapse and infection remained as major causes of death. Studies evaluating institutional trends in patients undergoing HSCT and analyzing their mortality profile, can improve the management of patients, leading to a reduction in transplant-related problems.

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.

Total nucleated cell dose in graft is a better prognostic factor for survival in pediatric patients transplanted with bone marrow compared to CD34+, CD3+, or total mononuclear cell count.

BACKGROUND: Most studies investigating the impact of graft composition on transplant-related outcomes have focused on the effect of CD34+ cell dose and reported equivocal results. The aim of this study is to investigate the impact of doses of total nucleated cells (TNCs), total mononuclear cells (TMCs), CD3+, and CD34+ cells on the outcome of children receiving allogeneic hematopoietic stem cell transplantation (HSCT). METHODS: Children and adolescents who underwent allogeneic HSCT for malignant hemato-oncological diseases or nonmalignant diseases in Cukurova University Faculty of Medicine, Pediatric Bone Marrow Transplantation Center between 2010 and 2020 were enrolled in the study. RESULTS: A total of 212 patients receiving allogeneic HSCT (154 bone marrow transplantation; 58 peripheral blood stem cell transplantation) from matched related or unrelated donors were included in the study. Higher TNC doses associated with a superior 5-year event-free survival (EFS; 67.7% vs 44.7%) in the whole group (log-rank P = .027). Overall survival (OS) and EFS of bone marrow-transplanted patients differed significantly according to TNC doses (log-rank P = .041 and .027, respectively). Multivariant analysis for OS revealed a P value of .038 for TNC, Exp(B) = 1.939 (95% CI: [1.038, 3.621]). That for EFS revealed a P value of .025 for TNC, Exp(B) = 1.992 (95% CI: [1.088, 3.647]). There was no relationship between doses of CD34+ cells, CD3+ cells, TMC, TNC, and neutrophil or platelet engraftment. CONCLUSION: Our data suggest that TNC dose is a better prognostic factor for pediatric allogeneic HSCT outcomes than doses of CD34+ cells, CD3+ cells, or TMC in patients transplanted with bone marrow. Future studies analyzing cell subsets and other components in TNC could elaborate the factor(s) accompanying this observed survival advantage.

Risks and outcomes of invasive fungal infections in pediatric allogeneic hematopoietic stem cell transplant recipients receiving fluconazole prophylaxis: a multicenter cohort study by the Turkish Pediatric Bone Marrow Transplantation Study Group.

Invasive fungal infections (IFIs) are a major cause of infection-related morbidity and mortality in patients undergoing allogeneic hematopoietic stem cell transplantation (HSCT). Data from pediatric settings are scarce. To determine the incidence, risk factors and outcomes of IFIs in a 180-day period post-transplantation, 408 pediatric patients who underwent allogeneic HSCT were retrospectively analyzed. The study included only proven and probable IFIs. The cumulative incidences of IFI were 2.7%, 5.0%, and 6.5% at 30, 100, and 180 days post-transplantation, respectively. According to the multivariate analysis, the factors associated with increased IFI risk in the 180-day period post-HSCT were previous HSCT history (hazard ratio [HR], 4.57; 95% confidence interval [CI] 1.42-14.71; P = .011), use of anti-thymocyte globulin (ATG) (HR, 2.94; 95% CI 1.27-6.80; P = .012), grade III-IV acute graft-versus-host-disease (GVHD) (HR, 2.91; 95% CI 1.24-6.80; P = .014) and late or no lymphocyte engraftment (HR, 2.71; 95% CI 1.30-5.62; P = .007). CMV reactivation was marginally associated with an increased risk of IFI development (HR, 1.91; 95% CI 0.97-3.74; P = .063). IFI-related mortality was 1.5%, and case fatality rate was 27.0%.The close monitoring of IFIs in pediatric patients with severe acute GVHD who receive ATG during conditioning is critical to reduce morbidity and mortality after allogeneic HSCT, particularly among those with prior HSCT and no or late lymphocyte engraftment.

Outcome of autologous hematopoietic stem cell transplantation in children and adolescents with relapsed or refractory Hodgkin's lymphoma.

This study evaluates the outcome of 66 pediatric patients with rrHL who underwent autoHSCT. Twenty-nine patients experienced early relapse, and 19 patients experienced late relapse. Of 18 newly diagnosed with HL, 13 were primary refractory disease and five had late responsive disease. At the time of transplantation, only 68% of the patients were chemosensitive. The majority of patients received BCNU + etoposide + ara-C + melphalan for conditioning (45/66), and peripheral blood (56/66) was used as a source of stem cells. After a median follow-up period of 39 months, 46 patients were alive. At five yr, the probabilities of OS, EFS, the relapse rate, and the non-relapse mortality rate were 63.1%, 54.3%, 36.4%, and 9.1%, respectively. The probability of EFS in chemosensitive and chemoresistant patients at five yr was 72.3% and 19%, respectively (p < 0.001). Multivariate analysis showed that chemoresistant disease at the time of transplantation was the only factor predicting limited both OS (hazard ratio = 4.073) and EFS (hazard ratio = 4.599). AutoHSCT plays an important role for the treatment of rrHL in children and adolescents, and survival rates are better for patients with chemosensitive disease at the time of transplantation.

Replacing actinomycin-D with Carboplatin for newly diagnosed rhabdomyosarcoma.

BACKGROUND: Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma in the pediatric age group. All patients with RMS regardless of their initial stage or group receive combination chemotherapy as 'standard therapy' consisting of vincristine, actinomycin-D and cyclophosphamide. Actinomycin-D was not readily available in Turkey at one time. Carboplatin was used instead in order to prevent delays in treatment. The aim of this report is to present the results of patients with rhabdomyosarcoma receiving carboplatin or actinomycin-D therapy. MATERIALS AND METHODS: Twenty four patients with rhabdomyosarcoma treated between December 2000 and June 2011 were included in this retrospective study. The patients were treated according to International Rhabdomyosarcoma Study Group guidelines. Eleven patients were treated with actinomycin-D and 13 with carboplatin (250 mg/m2/dose for 2 days). The two groups were then compared in terms of 2- and 5-year overall survival (OS) and hematological and non-hematological toxicities. RESULTS: Age, sex, stage and the mean duration of follow-up were similar in both groups (p>0.05 ). Two- and five-year OS levels were 68.2% in the carboplatin group and 78.0% and 40.0%, respectively, in the actinomycin-D group. There was no statistical difference in the number of febrile episodes (p=0.86 ) and no other hematological and non-hematological adverse effects were recorded in both groups. CONCLUSIONS: The findings show that carboplatin can be used as an alternative drug in the primary treatment of rhabdomyosarcoma in the event that actinomycin-D is unavailable or not tolerated.

Meropenem versus piperacillin-tazobactam as empiric therapy for febrile neutropenia in pediatric oncology patients.

BACKGROUND: Infection is a serious cause of mortality in febrile neutropenia of pediatric cancer patients. Recently, monotherapy has replaced the combination therapy in empirical treatment of febrile neutropenia. Since there has been no reported trial comparing the efficacy of meropenem and piperacillin-tazobactam (PIP/ TAZ) monotherapies, the present retrospective study was conducted to compare safety and efficacy in febrile neutropenic children with cancer. MATERIALS AND METHODS: Charts of febrile, neutropenic children hospitalized at our center between March 2008 and April 2011 for hemato-oncological malignancies were reviewed. Patients received PIP/TAZ 360 mg/kg/day or meropenem 60 mg/kg/day intravenously in three divided doses. Duration of fever and neutropenia, absolute neutrophil count, modification, and success rate were compared between the two groups. Resolution of fever without antibiotic change was defined as success and resolution of fever with antibiotic change or death of a patient was defined as failure. Modification was defined as changing the empirical antimicrobial agent during a febrile episode. RESULTS: Two hundred eighty four febrile neutropenic episodes were documented in 136 patients with a median age of 5 years. In 198 episodes meropenem and in 86 episodes PIP/ TAZ were used. Duration of fever and neutropenia, neutrophil count, sex, and primary disease were not different between two groups. Success rates and modification rate between two groups showed no significant differences (p>0.05). Overall success rate in the meropenem and PIP/TAZ groups were 92.4% and 91.9% respectively. No serious adverse effects occurred in either of the groups. CONCLUSIONS: Meropenem and PIP/TAZ monotherapy are equally safe and effective in the initial treatment of febrile neutropenia in children with cancer.

Treatment of Wilms tumor using carboplatin compared to therapy without carboplatin.

BACKGROUND: Wilms tumor (WT) is the most common pediatric malignant primary renal tumor. One of the main drugs used in treatment is actinomycin-D. This was not readily available in Turkey at one time. Carboplatin was used in the primary treatment of WT in order to prevent delays in treatment. The aim of this study is to present the results of patients with WT receiving carboplatin or actinomycin-D therapy. PROCEDURE: Forty-eight consecutive patients with WT treated between July 2005 and December 2011 were included in this retrospective study. The patients were treated according to Turkish Pediatric Oncology Group guidelines. Nineteen patients were treated with actinomycin-D and 29 with carboplatin (500 mg/m(2) /dose). The two groups were then compared in terms of 2- and 4-year overall survival (OS), event-free survival (EFS) and disease-free survival (DFS). RESULTS: Two- and four-year OS rates in the carboplatin group were 90.0% and 90.0%, compared to 100.0% and 88.0%, respectively, in the non-carboplatin group. Two- and four-year EFS levels in the carboplatin group were 92.0% and 88.0%, respectively, compared to 82.0% and 76.0% in the non-carboplatin group. Two-and four-year DFS levels in the carboplatin group were 92.0% and 86.0%, respectively, compared to 77.0% and 77.0% in the non-carboplatin group. CONCLUSIONS: The findings show that the carboplatin can be used as an alternative drug in the primary treatment of WT in the event that actinomycin-D is unavailable or not tolerated.

Leukemoid reaction associated with pediatric nasopharyngeal carcinoma: An unusual presentation.

Nasopharyngeal carcinoma is a tumor originating from the surface epithelial cells of nasopharynx. It is rare in children and adolescents. Most common physical finding is a neck mass. Most children with nasopharyngeal carcinoma present with advanced stage disease. The presentation with hematological abnormalities in patients without systemic metastasis is extremely rare. We reported a 14-year-old boy presenting with a mass at the right side of the pharynx and leukemoid reaction. To our knowledge, this is the first report of leukemoid reaction associated with pediatric nasopharyngeal carcinoma in English literature.

The protective effect of hesperidin on methotrexate-induced intestinal epithelial damage in rats: an experimental study.

OBJECTIVE: The purpose of this experimental study was to evaluate the efficacy of hesperidin (HES) in protecting against methotrexate (MTX)-induced intestinal damage using histopathological and immunohistochemical techniques. MATERIALS AND METHODS: Seventy-eight male Wistar albino rats were divided into 4 groups that received (a) saline only (control group), n = 19; (b) HES only, n = 19; (c) MTX only, n = 19, and (d) MTX plus HES, n = 21. On the first day of the study, a single dose of MTX (20 mg/kg) was administered intraperitoneally to group 3 and 4 rats. The HES (200 mg/kg) was administered by gavage for 5 days. For the MTX plus HES group, HES (200 mg/kg) was administered by gavage for 5 days after MTX treatment. Rats were sacrificed on the 2nd, 4th and 6th day of the study. Tissue samples from the jejunum were taken for histopathological and immunohistochemical analysis. RESULTS: On the 4th day, crypt injury in the MTX plus HES group (1.00 ± 0.00) was less than that in the MTX group (2.00 ± 0.89; p < 0.05). The small intestinal damage score was lower in the MTX plus HES group (6.33 ± 0.82) as compared to the MTX group (8.00 ± 2.37). Inducible nitric oxide synthase and interleukin-8 levels were lower in the MTX plus HES group (65 and 25%, respectively) as compared to the corresponding values of the MTX group (80 and 52.5%, respectively). On the 6th day, the Ki-67 proliferation index in the MTX group (45%) was lower than that in the MTX plus HES group (76.67%) and the control group (p < 0.05). The small intestinal damage score was high in the HES group on the 4th day due to increased cellular infiltration. On the 6th day, the Ki-67 proliferation index rose in parallel with the decrease in cellular infiltration and therefore histopathological scoring. The proliferation-enhancing effect of HES also appeared in healthy rats. CONCLUSION: HES seemed to have a protective effect against MTX-induced intestinal injury.

Dermatopathic lymphadenitis associated with human papilloma virus infection and verruca vulgaris.

Here we present a pediatric case of human papilloma virus associated with dermatopathic lymphadenitis (DL). A 5-year-old boy presented to the pediatric oncology clinic with swelling of the neck and warts on his lower jaw. His blood chemistry and complete blood count were normal, as was chest x-ray. HIV, EBV, CMV, and parvovirus serologies were negative. The patient was investigated for malignancy and lymphoma but no association was found. Histopathologic examination of the lymph node and the lesion revealed DL and verruca vulgaris, respectively. DL represents a benign form of reactive lymph node hyperplasia and described in patients with HIV and EBV infections. It is a rare entity described in patients with human papilloma virus infection. To our knowledge, this is the first report of DL in a patient with human papilloma virus infection.

Mesenchymal stem cell: does it work in an experimental model with acute respiratory distress syndrome?

We hypothesized that bone marrow-derived mesenchymal stem cells (BM-MSCs) would have a possible role in the treatment of acute respiratory distress syndrome (ARDS). ARDS disease model was developed in Wistar albino male rats by intratracheal instillation of physiological saline solution. Anesthezied and tracheotomized rats (n = 8) with ARDS were pressure-controlled ventilated. Isolated and characterized rat (r-) BM-MSCs were labeled with GFP gene, and introduced in the lungs of the ARDS rat-model. After applying of MSCs, the life span of each rat was recorded. When rats died, their lung tissues were removed for histopathological examination. Also the tissue sections were analyzed for GFP labeled rBM-MSCs and stained for vimentin, CK19, proinflammatory (MPO, IL-1ß, IL-6 and MIP-2) and anti-inflammatory [IL-1ra and prostaglandin E2 receptor (EP3)] cytokines. The histopathological signs of rat-model ARDS were similar to the acute phase of ARDS in humans. rBM-MSCs were observed to home in lung paranchyma. Although the infiltration of neutrophils slightly decreased in the interalveolar, peribronchial and perivascular area, a notable improvement was determined in the degree of hemorrhage, edema and hyaline membrane formation in rats treated with rBM-MSCs. Also decreased proinflammatory cytokines levels and increased the intensity of anti-inflammatory cytokines were established. Therefore MSCs could promote alveolar epithelial repair by mediating of cytokines from a proinflammatory to an anti-inflammatory response. As a novel therapeutic approach, mesenchymal stem cell treatment with intratracheal injection could be helpful in the management of critically ill patients with ARDS.

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.

Pediatric invasive mucormycosis cured with high dose liposomal amphotericin B.

Amphotericin B remains the mainstay medical treatment of pulmonary mucormycosis. Optimal dose is not defined. We described a case of pulmonary mucormycosis, which had been treated with 42.55 g (during to 45 weeks) liposomal amphotericin B. In medical literature this case is one of the highest doses of lyposomal amphotericin B administered to a pediatric patient.

Chromosome imbalances and alterations of AURKA and MYCN genes in children with neuroblastoma.

BACKGROUND: Neuroblastoma (NB), like most human cancers, is characterized by genomic instability, manifested at the chromosomal level as allelic gain, loss or rearrangement. Genetics methods, as well as conventional and molecular cytogenetics may provide valuable clues for the identification of target loci and successful search for major genes in neuroblastoma. We aimed to investigate AURKA and MYCN gene rearrangements and the chromosomal aberrations (CAs) to determine the prognosis of neuroblastoma. METHODS: We performed cytogenetic analysis by G-banding in 25 cases [11 girls (44%) and 14 boys (66%)] and in 25 controls. Fluorescence in situ hybridization (FISH) with AURKA and MYCN gene probes was also used on interphase nuclei to screen for alterations. RESULTS: Some 18.4% of patient cells exhibited CAs., with a significant difference between patient and control groups in the frequencies (P<0.0001). Some 72% of the cells had structural aberrations, and only 28% had numerical chnages in patients. Structural aberrations consisted of deletions, translocations, breaks and fragility in various chromosomes, 84% and 52% of the patients having deletions and translocations, respectively. Among these expressed CAs, there was a higher frequency at 1q21, 1q32, 2q21, 2q31, 2p24, 4q31, 9q11, 9q22, 13q14, 14q11.2, 14q24, and 15q22 in patients. 32% of the patients had chromosome breaks, most frequently in chromosomes 1, 2, 3, 4, 5, 8, 9, 11, 12, 19 and X. The number of cells with breaks and the genomic damage frequencies were higher in patients (p<0.001). Aneuploidies in chromosomes X, 22, 3, 17 and 18 were most frequently observed. Numerical chromosome abnormalities were distinctive in 10.7% of sex chromosomes. Fragile sites were observed in 16% of our patients. CONCLUSION: Our data confirmed that there is a close correlation between amplification of the two genes, amplification of MYCN possibly contributing significantly to the oncogenic properties of AURKA. The high frequencies of chromosomal aberrations and amplifications of AURKA and MYCN genes indicate prognostic value in children with neuroblastomas and may point to contributing factors in their development.

Brain natriuretic peptide levels in pediatric cancer patients with febrile neutropenia.

Brain natriuretic peptide (BNP) is considered as a prognostic marker in patients with sepsis, but no data are available on BNP in pediatric cancer patients with febrile neutropenia (FN). Twenty-five pediatric cancer patients with FN were included in this study. Serum BNP level was measured. The mean BNP level was 330.8 ± 765.3 pg/mL (5.9-3806 pg/mL). BNP levels of 12 patients were found over the normal level. High BNP levels were related to some conditions of the patients, and these were statistically significant (P < .05). These conditions were required erythrocyte suspension, had pneumonia, time stayed in hospital, and neutropenia time. When regression test was done, required erythrocyte suspension for anemia and had pneumonia were found to be statistically significant. In conclusion, this is one of the first studies on BNP levels in pediatric cancer patients with FN. However, further studies with large sample sizes are needed to confirm the results and provide new data about this issue.

Fms-like tyrosine kinase 3 mutations in childhood acute leukemias and their association with prognosis.

INTRODUCTION: In recent years, Fms-like tyrosine kinase (FLT) 3 has been the subject of several studies as a prognostic marker. OBJECTIVE: In this study, the presence of FLT3 mutations in childhood acute leukemias patients and their association with prognosis were investigated. MATERIALS AND METHODS: A total of 120 patients, 80 with acute lymphoblastic leukemia (ALL) and 40 with acute myeloblastic leukemia (AML), were included. Real time polymerase chain reaction methods on a high resolution melting analysis device were used to determine FLT3 mutations. RESULTS: FLT3/ITD (internal tandem duplication) mutations were found in 6 (7.5%) of the patients with ALL and in 9 (22.5%) of those with AML, whereas no FLT3/TKD (trans kinase domain) mutation was evident in any case. There was no difference between the ALL patients positive and negative for FLT3/ITD with regard to overall survival (OS), event free survival (EFS) and disease free survival (DFS) (p=0.37, p=0.23, p=0.023, respectively). However, in FLT3/ITD positive and negative AML patients, there was a statistically significant difference in OS (p=0.0041), but not EFS and DFS (p=0.09, p=0.095, respectively). A significant difference was found between age and FLT3/ITD positivity (p=0.036). CONCLUSION: We found that FLT3/ITD positivity increased with age and that it was associated with decrease in OS in AML patients, providing further evidence that it is an independent factor negatively influencing prognosis.