Genomic insights into inherited bone marrow failure syndromes in a Korean population.

Inherited bone marrow failure syndromes (IBMFS) pose significant diagnostic challenges due to overlapping symptoms and variable expressivity, despite evolving genomic insights. The study aimed to elucidate the genomic landscape among 130 Korean patients with IBMFS. We conducted targeted next-generation sequencing (NGS) and clinical exome sequencing (CES) across the cohort, complemented by whole genome sequencing (WGS) and chromosomal microarray (CMA) in 12 and 47 cases, respectively, with negative initial results. Notably, 50% (n = 65) of our cohort achieved a genomic diagnosis. Among these, 35 patients exhibited mutations associated with classic IBMFSs (n = 33) and the recently defined IBMFS, aplastic anaemia, mental retardation and dwarfism syndrome (AmeDS, n = 2). Classic IBMFSs were predominantly detected via targeted NGS (85%, n = 28) and CES (88%, n = 29), whereas AMeDS was exclusively identified through CES. Both CMA and WGS aided in identifying copy number variations (n = 2) and mutations in previously unexplored regions (n = 2). Additionally, 30 patients were diagnosed with other congenital diseases, encompassing 13 distinct entities including inherited thrombocytopenia (n = 12), myeloid neoplasms with germline predisposition (n = 8), congenital immune disorders (n = 7) and miscellaneous genomic conditions (n = 3). CES was particularly effective in revealing these diverse diagnoses. Our findings underscore the significance of comprehensive genomic analysis in IBMFS, highlighting the need for ongoing exploration in this complex field.

Front-Line Tyrosine Kinase Inhibitors in Pediatric Chronic Myeloid Leukemia: A Study on Efficacy and Safety.

We conducted a retrospective study on 51 pediatric patients with newly diagnosed chronic myeloid leukemia chronic phase or accelerated phase. The patients were classified into the IMA group (N = 33), treated with imatinib, and the DSA group (N = 18), treated with dasatinib, as front-line tyrosine kinase inhibitors (TKIs). At 12 months, the rates of complete cytogenetic response were similar between the IMA group (92.3%) and DSA group (100%) (p = 0.305). However, the rate of early molecular response was higher in the DSA group than in the IMA group (100.0% vs. 80.0%, p = 0.043). By 12 and 24 months, the DSA group showed faster and higher cumulative rates of both major (DSA group: 72.2% and 100%, respectively; IMA group: 41.2% and 68.7%, respectively; p = 0.002) and deep molecular responses (DSA group: 26.0% and 43.6%, respectively; IMA group: 13.8% and 17.5%, respectively; p = 0.004). Both TKIs were well tolerated. Although the height standard deviation scores decreased in both groups, the height decline was greater in the DSA group between one and two years from the start of TKI therapy. In this study, dasatinib achieved faster and higher molecular responses with an acceptable safety profile. Further follow-up is necessary to assess the long-term outcomes of TKI treatment in children.

Case report: First report of isolated central nervous system lymphoblastic crisis in a child with chronic myeloid leukemia on dasatinib therapy.

Most children with chronic myeloid leukemia (CML) present with the chronic phase (CML-CP) at diagnosis, exhibiting an excellent treatment response to contemporary tyrosine kinase inhibitors (TKIs). However, despite TKI therapy, patients with CML-CP may progress to blastic crisis (BC). CML-BC rarely occurs in extramedullary sites, and isolated central nervous system (CNS) BC is an extremely rare condition. It may with present various neurologic symptoms that necessitates differential diagnosis from other causes such as TKI toxicity. Information on the diagnosis and treatment of this condition is lacking, as are well-established diagnostic criteria. Here, we report a case of isolated CNS lymphoblastic crisis in a child with CML-CP who was treated with dasatinib. The patient, an 8-year-old girl, was admitted owing to visual disturbance and severe headache. We highlight the importance of a CSF study for the differential diagnosis of CNS BC in patients with CML-CP who present with common neurologic symptoms during TKI therapy.

Epidemiologic and Clinical Outcomes of Pediatric Renal Tumors in Korea: A Retrospective Analysis of The Korean Pediatric Hematology and Oncology Group (KPHOG) Data.

PURPOSE: Renal tumors account for approximately 7% of all childhood cancers. These include Wilms tumor (WT), clear cell sarcoma of the kidney (CCSK), malignant rhabdoid tumor of the kidney (MRTK), renal cell carcinoma (RCC), congenital mesoblastic nephroma (CMN) and other rare tumors. We investigated the epidemiology of pediatric renal tumors in Korea. MATERIALS AND METHODS: From January 2001 to December 2015, data of pediatric patients (0-18 years) newly-diagnosed with renal tumors at 26 hospitals were retrospectively analyzed. RESULTS: Among 439 patients (male, 240), the most common tumor was WT (n=342, 77.9%), followed by RCC (n=36, 8.2%), CCSK (n=24, 5.5%), MRTK (n=16, 3.6%), CMN (n=12, 2.7%), and others (n=9, 2.1%). Median age at diagnosis was 27.1 months (range 0-225.5) and median follow-up duration was 88.5 months (range 0-211.6). Overall, 32 patients died, of whom 17, 11, 1, and 3 died of relapse, progressive disease, second malignant neoplasm, and treatment-related mortality. Five-year overall survival and event free survival were 97.2% and 84.8% in WT, 90.6% and 82.1% in RCC, 81.1% and 63.6% in CCSK, 60.3% and 56.2% in MRTK, and 100% and 91.7% in CMN, respectively (p < 0.001). CONCLUSION: The pediatric renal tumor types in Korea are similar to those previously reported in other countries. WT accounted for a large proportion and survival was excellent. Non-Wilms renal tumors included a variety of tumors and showed inferior outcome, especially MRTK. Further efforts are necessary to optimize the treatment and analyze the genetic characteristics of pediatric renal tumors in Korea.

Short-term effect of growth hormone treatment in childhood leukemia survivors with growth hormone deficiency.

PURPOSE: Survivors of childhood leukemia are at risk of growth impairment due to intensive chemotherapy and radiation treatments. This study investigated the auxological and biochemical characteristics of childhood leukemia survivors diagnosed with growth hormone deficiency (GHD) and the changes in these parameters after 1 year of growth hormone (GH) treatment. METHODS: A total of 24 children diagnosed with GHD after leukemia treatment was analyzed. Clinical and biochemical data were collected retrospectively at leukemia diagnosis, GHD diagnosis, and 1 year after GH treatment. Standard deviation score (SDS) was calculated based on the age- and gender-adjusted population. RESULTS: Of the 24 children included in this study, 19 received GH treatment. The median age at GHD diagnosis was 12.3 years, and the median delay in bone age was 1.46 years. Height SDS decreased from -0.69 at leukemia diagnosis to -2.58 at GHD diagnosis (P<0.001). The change in height SDS with and without GH for 1 year was 0.35 and -0.21, respectively (P=0.044). In regression analyses, higher height SDS at GHD diagnosis and a smaller decrease of the height SDS between leukemia and GHD diagnoses were positively correlated with height SDS after GH treatment. CONCLUSION: GH treatment could be beneficial and safe for improving height in childhood leukemia survivors with GHD. Height SDS at GHD diagnosis and reduction of height SDS between leukemia and GHD diagnosis could be potential factors in predicting the therapeutic effects. Close auxological monitoring is recommended for any childhood leukemia survivors who experience posttreatment height decline.

Factors affecting bone mineral density in children and adolescents with secondary osteoporosis.

PURPOSE: This study aimed to investigate the clinical factors associated with bone mineral density (BMD) among children and adolescents with osteoporosis secondary to treatment for underlying clinical conditions. METHODS: We retrospectively reviewed the medical records of patients aged 10-18 years and evaluated them for lumbar spine BMD (LSBMD) after treatment for underlying diseases, including hemato-oncologic, rheumatologic system, and inflammator y bowel diseases. LSBMD measured by dual-energy x-ray absorptiometry (DXA) performed from March 2019 to March 2021 was evaluated. We analyzed 117 patients who underwent initial DXA after treatment for underlying diseases. RESULTS: Subjects in this study had multiple underlying diseases: hemato-oncologic (78.6%), rheumatologic (11.1%), and inflammatory bowel diseases (10.3%). There was no significant association between the z-score and bone metabolic markers (P>0.05). However, higher cumulative glucocorticoid (GC) dose significantly reduced LSBMD z-score (P=0.029). Moreover, the association between cumulative dose of GC and initial z-score of LSBMD was significant in logarithmic regression analysis (P=0.003, R2=0.149). GC accumulation was a significant risk factor for vertebral fracture when the initial BMD was evaluated after treatment (P=0.043). Bone metabolic markers did not significantly influence the risk of vertebral fracture. CONCLUSION: Initial bone mass density of the lumbar spine evaluated after long-term GC use for underlying diseases is a predictor of further vertebral fractures.

Prognostic impact of total body irradiation dose in pediatric acute lymphoblastic leukemia patients treated with allogeneic hematopoietic stem cell transplantation in second complete remission.

Background: Allogeneic HSCT may improve survival in pediatric ALL patients who relapse. In this study, we analyzed the outcome and prognostic factors of 62 ALL patients (35 male, 56.5%) who received allogeneic HSCT in second complete remission (CR) at our institution between April 1st 2009 and December 31st 2019. Methods: The median time from diagnosis to relapse was 35.1 months (range, 6.0‒113.6 mo). Fifty-three patients (85.5%) experienced bone marrow relapse only. The number of patients who received transplant according to each donor type was as follows: HLA matched family donor 17 (27.4%), matched unrelated donor (UD) 22 (35.5%), mismatched donor 23 (37.1%). All patients received HSCT with a myeloablative conditioning, 58 patients (93.5%) with the incorporation of TBI [31 patients 12 Gray (Gy), 24 patients 13.2 Gy, 3 patients 8 Gy]. Results: The 5-year event-free survival (EFS), and overall survival of the study group was 41.3±6.3% (26/62), and 42.3±6.6% (27/62), respectively. The cumulative incidence of relapse and transplant-related mortality was 57.1±6.4% and 1.6±1.6%, respectively. Infant ALL, shorter time from diagnosis to relapse, and TBI dose of 12 Gy, rather than 13.2 Gy, resulted in significantly worse EFS. In multivariate analysis, infant ALL and TBI dose of 12 Gy during conditioning predicted significantly lower EFS. Conclusion: In our study group, treatment with a higher dose of TBI during conditioning resulted in better EFS for ALL patients who underwent HSCT in second CR. Further study is needed to determine potential long-term complications associated with a higher TBI dose.

Spectrum of Genetic Mutations in Korean Pediatric Acute Lymphoblastic Leukemia.

The wide application of next-generation sequencing (NGS) technologies has led to the discovery of multiple genetic alterations in pediatric acute lymphoblastic leukemia (ALL). In this work, we aimed to investigate the mutational spectrum in pediatric ALL. We employed a St. Mary's customized NGS panel comprising 67 leukemia-related genes. Samples were collected from 139 pediatric ALL patients. Eighty-five patients (61.2%) harbored at least one mutation. In B-cell ALL, the RAS pathway is the most involved pathway, and the three most frequently mutated genes were NRAS (22.4%), KRAS (19.6%), and PTPN11 (8.4%). NRAS and PTPN11 were significantly associated with a high hyperdiploidy karyotype (p = 0.018 and p < 0.001, respectively). In T-cell ALL, the three most frequently mutated genes were NOTCH1 (37.5%), FBXW7 (16.6%), and PTEN (6.2%). Several pairs of co-occurring mutations were found: NRAS with SETD, NRAS with PTPN11 in B-cell ALL (p = 0.024 and p = 0.020, respectively), and NOTCH1 with FBXW7 in T-cell ALL (p < 0.001). The most frequent newly emerged mutation in relapsed ALL was NT5C2. We procured comprehensive genetic information regarding Korean pediatric ALL using NGS technology. Our findings strengthen the current knowledge of recurrent somatic mutations in pediatric ALL.

Clinical implication of minimal residual disease assessment by next-generation sequencing-based immunoglobulin clonality assay in pediatric B-acute lymphoblastic leukemia.

Measuring minimal residual disease (MRD) during treatment is valuable to identify acute lymphoblastic leukemia (ALL) patients who require intensified treatment to avert relapse. We performed the next-generation sequencing (NGS)-based immunoglobulin gene (Ig) clonality assay and evaluated its clinical implication in pediatric B-ALL patients to assess MRD. Fifty-five patients who were diagnosed and treated with de novo (n = 44) or relapsed/refractory B-ALL (n = 11) were enrolled. MRD assessment was performed using the LymphoTrack® Dx IGH and IGK assay panels. The percentage of the clonal sequences per total read count was calculated as MRD (% of B cells). The data were normalized as the proportion of total nucleated cells (TNC) by LymphoQuant™ Internal control or the B-cell proportion in each sample estimated by flow cytometry or immunohistochemistry. Clonal Ig rearrangement was identified in all patients. The normalized MRD value was significantly lower than the unnormalized MRD value (p < 0.001). When categorizing patients, 27 of 50 patients (54%) achieved normalized MRD <0.01%, while 6 of them did not achieve MRD <0.01% when applying the unnormalized value. The normalized post-induction MRD value of 0.01% proved to be a significant threshold value for both 3-year event-free survival (100% for MRD <0.01% vs. 60.9% ± 10.2% for MRD ≥0.01%, p = 0.007) and 3-year overall survival (100% for MRD <0.01% vs. 78.3% ± 8.6% for MRD ≥0.01%, p = 0.011). However, unnormalized MRD was not a significant factor for outcome in this cohort. Our study demonstrated that MRD assessment by NGS-based Ig clonality assay could be applied in most pediatric B-ALL patients. Normalized post-induction MRD <0.01% was a significant prognostic indicator.

Discontinuation of tyrosine kinase inhibitors based on BCR-ABL1 monitoring by digital droplet PCR in pediatric chronic myeloid leukemia.

Lifelong treatment of pediatric chronic myeloid leukemia (CML) patients with tyrosine kinase inhibitors (TKIs) can affect their growth and development. For these reasons, clinical trials have explored the feasibility of TKI discontinuation in children with a sufficient TKI response. We evaluated the analytical performance of digital droplet PCR (ddPCR) to quantify BCR-ABL1 and compared the results with reverse transcription quantitative polymerase chain reaction (RT-qPCR). We further investigated whether ddPCR could be used to determine TKI discontinuation in a clinical setting. Performance of ddPCR was evaluated using standard materials for BCR-ABL1, and a total of 197 clinical samples from 45 pediatric CML patients was included for comparison with RT-qPCR. ddPCR showed excellent analytical sensitivity with 0.001% international scale (IS) and linearity with R 2 > 0.99 in log scale. BCR-ABL1 % IS results correlated well with those of RT-qPCR (R 2 = 0.9435), however, they showed a moderate strength for agreement with a Cohen's kappa of 0.41 due to higher sensitivity of ddPCR. Among 45 pediatric CML patients, 42 were treated with first-line TKIs including imatinib (n = 27, 64%) and dasatinib (n = 12, 29%), and three patients that were started with imatinib were switched to dasatinib. When we evaluated whether follow-up samples fulfilled ABL1 copies ≥ 10,000 required for deep molecular response (DMR), all samples were acceptable by ddPCR, whereas 18% by RT-qPCR did not reached acceptable ABL1 copies. Moreover, 52 and 13% reached ABL1 copies ≥ 32,000 required for MR4.5 by ddPCR and RT-qPCR, respectively. Seven patients discontinued TKI and the median TKI treatment duration was 73 months prior to discontinuation. Prior to discontinuation, the median duration of sustained undetected BCR-ABL1 was 60 months. Two patients experienced loss of major MR (MMR) during follow-up and restarted dasatinib 5 months after discontinuation. They achieved MMR again and maintained better than DMR afterward. Results from those patients demonstrated that RT-qPCR did not match the need for adequate ABL1 copies for MR4.5 while majority of ddPCR could. Therefore, ddPCR was technically more acceptable to decide and monitor pediatric CML patients before and after TKI discontinuation.

Extramedullary Infiltration in Pediatric Acute Myeloid Leukemia on Surveillance Magnetic Resonance Imaging and its Relationship With Established Risk Factors.

PURPOSE: Extramedullary infiltration (EMI) is a rare condition defined by the accumulation of myeloid tumor cells beyond the bone marrow. The clinical significance is still controversial. This study was aimed to evaluate the incidence, characteristics, and prognostic significance of EMI on complete magnetic resonance imaging (MRI) investigation in newly diagnosed pediatric acute myeloid leukemia (AML) patients who are asymptomatic without clinical evidence to suspect EMI. MATERIALS AND METHODS: Retrospective clinical and radiologic review of 121 patients with MRI examination at the time of initial diagnosis of AML without any clinical evidence suggestive of EMI was performed. Patients were divided into 2 groups according to the presence or absence of EMI, and the relationship between EMI and established risk factors was analyzed. Initial white blood cell count, the occurrence of an event (including relapse, death, and primary refractory disease), survival status, and detailed information on cytogenetic/molecular status was performed by a thorough review of electronic medical records system. All patients underwent full imaging evaluation with the contrast-enhanced whole body and some regional MRI at the time of initial diagnosis. RESULTS: The median age at diagnosis was 10.77 years (range, 0.37 to 18.83 y). Based on the risk stratification system of AML, 36, 45, and 40 patients are classified as low-risk, intermediate-risk, and high-risk groups, respectively. MRI at the time of the initial diagnosis of AML revealed 35 of 121 patients (28.9%) with EMI. The most common site of EMI was a skull, followed by the lower extremity bone and meninges of the brain. The median age at diagnosis was significantly younger in patients with EMI (7.87 vs. 11.08 y, P=0.0212). Low incidence of FLT3/ITD mutation, low incidence of AML-ETO gene rearrangement, and the larger extent and more severe degree of bone marrow involvement was related with EMI. However, there was no significant prognostic difference in event-free survival and overall survival regardless of the presence of EMI in the overall patient population and each risk group. The location of EMI occurrence was also not related to prognosis. CONCLUSIONS: Even if EMI symptoms are not evident, surveillance MRI scans at the initial diagnosis of pediatric AML patients are very helpful in detecting a significant number of EMIs. Younger age, some molecular features, and more severe bone marrow involvement of AML patients were related with EMI. However, there was no significant prognostic difference between patients with or without EMI regardless of risk group. Further prospective investigation is necessary to validate the prognostic effect of EMI in a larger group of patients with different risk groups.

Management of immune thrombocytopenia: 2022 update of Korean experts recommendations.

Despite the availability of therapies to treat patients with immune thrombocytopenia (ITP), there is currently little data from randomized trials to assist clinicians in managing patients. The evidence-based guidelines of the Korean Society of Hematology Aplastic Anemia Working Party (KSHAAWP) are intended to support patients and physicians in the management of ITP. Experts from the KSHAAWP discussed and described this guideline according to the current treatment situation for ITP in Korea and finalized the guidelines. The expert panel recommended the management of ITP in adult and pediatric patients with newly diagnosed, persistent, and chronic disease refractory to first-line therapy with minor bleeding. Management approaches include observation and administration of corticosteroids, intravenous immunoglobulin, anti-D immunoglobulin, and thrombopoietin receptor agonists. Currently, evidence supporting strong recommendations for various management approaches is lacking. Therefore, a large focus was placed on shared decision-making, especially regarding second-line treatment.

High Failure-Free Survival after Unrelated Donor Peripheral Blood Stem Cell Transplantation in Pediatric Severe Aplastic Anemia.

The use of alternative donor peripheral blood stem cell transplantation (PBSCT) has increased in recent years. In this study, we analyzed the effect of stem cell source and HLA disparity on outcomes in pediatric patients with severe aplastic anemia (SAA). A total of 134 patients who underwent HSCT with nonmyeloablative conditioning between 2006 and 2020 were enrolled and classified into 3 groups: HLA-matched bone marrow transplantation (M-BMT; n = 24), HLA-matched PBSCT (M-PBSCT; n = 66), and HLA-mismatched PBSCT (MM-PBSCT; n = 44). Significantly higher stem cell doses were obtained for PBSCT than for BMT. A total of 13 patients experienced secondary graft failure (GF), with a cumulative incidence (CI) of 10.0%. HLA-mismatched PBSCT and a very severe degree of disease significantly decreased the incidence of secondary GF. The CI of grade II-IV acute graft-versus-host disease (GVHD) was significantly higher in PBSCT than in BMT, but the CI of grade III-IV acute GVHD and CI of chronic GVHD requiring systemic treatment did not increase in PBSCT. The estimated 5-year overall survival (OS), failure-free survival (FFS), and GVHD-free failure-free survival (GFFS) of the total cohort were 93.0%, 89.5%, and 77.5%, respectively. The most favorable FFS was observed in the MM-PBSCT group (97.6%; P = .03), whereas OS and GFFS were similar across the 3 groups. In multivariate analysis, HLA mismatch and short time from diagnosis to transplantation were associated with superior FFS. Unrelated donor PBSCT with low-intensity SAA conditioning showed favorable outcomes in terms of low rate of secondary GF, higher FFS, and manageable GVHD regardless of HLA compatibility. Our findings suggest the feasibility of PBSCT from unrelated donors, resulting in the possible expansion of the donor pool in transplantation for pediatric SAA. © 2021 American Society for Transplantation and Cellular Therapy. Published by Elsevier Inc.

Outcome of Intensive Therapy for Children with Relapsed Acute Myeloid Leukemia: A Single Institution Korean Study.

PURPOSE: Approximately 30%-40% of pediatric acute myeloid leukemia (AML) patients relapse. In this study, we analyzed the outcome and prognostic factors of relapsed AML patients who had previously received first-line therapy at our institution. MATERIALS AND METHODS: The study group consisted of 50 patients who had been diagnosed with AML from April 2009 to December 2018, and then showed first relapse. Thirty-two of the patients (64%) had previously received allogeneic hematopoietic stem cell transplantation (HSCT) in first complete remission (CR). RESULTS: Forty-five of the patients (90%) received intensive chemotherapy upon diagnosis of relapse, and 76% (34/45) of these patients achieved a second CR. Estimated 5-year overall survival for these 45 patients was 44.9%±7.6%. Time from diagnosis to relapse, extramedullary involvement (EMI) at diagnosis, core binding factor AML, and complex karyotype were significant prognostic factors; in multivariate study, both time from diagnosis to relapse and EMI at diagnosis proved significant. There was no difference in 5-year disease-free survival between patients previously treated with chemotherapy only and those who received HSCT in first CR (52.4%±14.9% vs. 52.6%±11.5%). Of the 19 patients who achieved second CR after previous allogeneic HSCT in first CR and subsequent relapse, 11 were treated with chemotherapy only, and seven survive disease-free. CONCLUSION: Intensive therapy allowed for long-term survival in 40%-50% of patients, and 50% of patients who achieved second CR, regardless of prior treatment modalities in first CR. Intensive treatment may allow for salvage of a significant portion of patients with relapsed pediatric AML.

Characteristics of RAS pathway mutations in juvenile myelomonocytic leukaemia: a single-institution study from Korea.

Juvenile myelomonocytic leukaemia (JMML), a rare clonal haematopoietic disorder of childhood, is characterised as a myelodysplastic/myeloproliferative neoplasm. Despite ground-breaking genetic discoveries, JMML remains difficult to diagnose given its diverse clinical features and disease course. A total of 24 patients with JMML were diagnosed and treated at a single institution, and their genetic profiles and association with clinical and laboratory characteristics were analysed. In all, 22 of the patients received allogeneic haematopoietic stem cell transplantation after myeloablative conditioning, mostly from a haploidentical family donor. RAS pathway mutations were identified in 88% of patients: PTPN11 [nine (38%)], NRAS [nine (38%)], KRAS [two (8%)], NF1 [five (21%)] and CBL [one (4%)]. Secondary mutations were found in 25% of patients: SETBP1, JAK3, ASXL1, GATA2, KIT, KDM6A, and BCOR. Six patients showed cytogenetic abnormalities, including three with monosomy 7. The estimated 5-year event-free survival (EFS) and overall survival (± standard error) of the entire cohort were 58·9 (10·9)% and 73·5 (10·8)% respectively. NRAS (+) patients had a higher 5-year EFS than NRAS (-) patients [72·9 (16·5)% vs. 52·5 (13·1)%, P = 0·127]. NRAS (+) patients had a better 5-year EFS than PTPN11 (+) patients [41·7 (17·3)%, P = 0·071]. Our study revealed the genetic characteristics of Korean JMML patients with RAS pathway and secondary mutations.

Effect of Vertebral Fracture on Auxological Profiles of Children Undergoing Acute Lymphoblastic Leukemia Treatment.

Background: Acute lymphoblastic leukemia (ALL) is the most common pediatric malignancy, and children with ALL often experience skeletal morbidity such as vertebral fractures (VF) during and after ALL treatment. Among various treatment-associated factors that affect growth pattern, the presence of VF might trigger growth impairment. Objective: This study aimed to investigate the overall VF incidence following childhood ALL treatment and examined the association of VF with growth. Methods: Children diagnosed with ALL whose treatment was completed between 2 and 15 years of age and who were screened with lateral thoracolumbar spine radiographs were enrolled. Clinical data, including anthropometric parameters were obtained at leukemia diagnosis (LD), treatment completion (TC), and 12 months following TC while VF assessment were obtained at TC and 12 months following TC. Results: In total, 155 children were included, and height status was decreased, whereas weight and BMI status were increased throughout three observational points. VF incidence at TC was 18.7%. Height status were lower in children with VF at LD, TC, and 12 months following TC, while a greater height decline was observed during the treatment period. Age and height status at LD and average glucocorticoid (GC) dose were associated VF incidence at TC. The presence of VF was a significant risk factor of height decline during the treatment period. Conclusion: A substantial number of children experienced VF following ALL treatment completion, and the presence of VF might adversely affect auxological status in children. VF detection by routine surveillance throughout childhood ALL treatment is recommended to try to prevent compromised growth.

Effectiveness and Safety of Clofarabine Monotherapy or Combination Treatment in Relapsed/Refractory Childhood Acute Lymphoblastic Leukemia: A Pragmatic, Non-interventional Study in Korea.

PURPOSE: Effectiveness and safety of clofarabine (one of the treatment mainstays in pediatric patients with relapsed/refractory acute lymphoblastic leukemia [ALL]) was assessed in Korean pediatric patients with ALL to facilitate conditional coverage with evidence development. MATERIALS AND METHODS: In this multicenter, prospective, observational study, patients receiving clofarabine as mono/combination therapy were followed up every 4-6 weeks for 6 months or until hematopoietic stem cell transplantation (HSCT). Response rates, survival outcomes, and adverse events were assessed. RESULTS: Sixty patients (2-26 years old; 65% B-cell ALL, received prior ≥ 2 regimen, 68.3% refractory to previous regimen) were enrolled and treated with at least one dose of clofarabine; of whom 26 (43.3%) completed 6 months of follow-up after the last dose of clofarabine. Fifty-eight patients (96.7%) received clofarabine combination therapy. Overall remission rate (complete remission [CR] or CR without platelet recovery [CRp]) was 45.0% (27/60; 95% confidence interval [CI], 32.4 to 57.6) and the overall response rate (CR, CRp, or partial remission [PR]) was 46.7% (28/60; 95% CI, 34.0 to 59.3), with 11 (18.3%), 16 (26.7%), and one (1.7%) patients achieving CR, CRp, and PR, respectively. The median time to remission was 5.1 weeks (95% CI, 4.7 to 6.1). Median duration of remission was 16.6 weeks (range, 2.0 to 167.6 weeks). Sixteen patients (26.7%) proceeded to HSCT. There were 24 deaths; 14 due to treatment-emergent adverse events. CONCLUSION: Remission with clofarabine was observed in approximately half of the study patients who had overall expected safety profile; however, there was no favorable long-term survival outcome in this study.

Erratum: Correction of Affiliations in the Article "Clinical Characteristics and Treatment Outcomes in Children, Adolescents, and Young-adults with Hodgkin's Lymphoma: a KPHOG Lymphoma Working-party, Multicenter, Retrospective Study".

This corrects the article on p. e393 in vol. 35, PMID: 33258329.