Duantida Songdej

Hematopoietic stem cell transplantation for homozygous β-thalassemia and β-thalassemia/hemoglobin E patients from haploidentical donors

Thalassemia-free survival after allogeneic stem cell transplantation (SCT) is about 80–90% with either matched-related or -unrelated donors. We explored the use of a mismatched-related (‘haplo- ’) donor. All patients received two courses of pretransplant immunosuppressive therapy (PTIS) with fludarabine (Flu) and dexamethasone (Dxm). After two courses of PTIS, a conditioning regimen of rabbit antithymocyte globulin, Flu and IV busulfan (Bu) was given followed by T-cell-replete peripheral blood progenitor cells. GvHD prophylaxis consisted of cyclophosphamide (Cy) on days SCT +3 and +4 (post-Cy), and on day SCT +5 tacrolimus or sirolimus was started together with a short course of mycophenolate mofetil. Thirty-one patients underwent haplo-SCT. Their median age was 10 years (range, 2–20 years). Twenty-nine patients engrafted with 100% donor chimerism. Two patients suffered primary graft failure. Median time to neutrophil engraftment was 14 days (range, 11–18 days). Five patients developed mild to moderate, reversible veno-occlusive disease, while nine patients developed acute GvHD grade II. Only five patients developed limited-chronic GvHD. Projected overall and event-free survival rates at 2 years are 95% and 94%, respectively. The median follow up time is 12 months (range, 7–33 months).

Cisplatin-induced ototoxicity in pediatric solid tumors: The role of glutathione S-transferases and megalin genetic polymorphisms

Cisplatin-induced ototoxicity, an important dose-limiting side effect, has proven high interindividual variability. Glutathione S-transferases (GSTs) are isoenzymes involved in cellular detoxification processes. Megalin has been demonstrated to bind aminoglycosides, known to be similar to cisplatin for their ototoxicity. The GSTs and megalin expression is genetically polymorphic, which might be responsible for the variability in cisplatin-induced ototoxicity. The genotyping of GSTM1, GSTT1 polymorphisms, and 2 nonsynonymous single nucleotide polymorphisms (SNPs) at megalin genes, rs2075252 and rs2228171, were performed in 68 children diagnosed with solid tumors who received cisplatin-based chemotherapy. After the end of treatment, audiometry demonstrated hearing loss in 79.4% of patients according to Brock classification. The cumulative cisplatin dose >400 mg/m2 is associated with increased risk of cisplatin-induced ototoxicity [odds ratio (OR), 17.5; 95% confidence interval (CI), 3.09-98.62]. GSTT1 wild genotype and C-allele of rs2228171 SNPs of megalin gene occurred with higher frequency in patients with ototoxicity (P=0.023; OR, 10; 95% CI, 1.80-56.00 and P=0.034; OR, 2.67; 95% CI, 1.22-5.82, respectively). In conclusion, our results suggested that GSTT1 wild genotype and C-allele of rs2228171 SNPs might be risk factors for ototoxicity. The cumulative cisplatin dose <400 mg/m2 should be beneficial in order to ameliorate ototoxicity.

Outcomes of Thalassemia Patients Undergoing Hematopoietic Stem Cell Transplantation by Using a Standard Myeloablative versus a Novel Reduced-Toxicity Conditioning Regimen According to a New Risk Stratification

Improving outcomes among class 3 thalassemia patients receiving allogeneic hematopoietic stem cell transplantations (HSCT) remains a challenge. Before HSCT, patients who were ≥ 7 years old and had a liver size ≥ 5 cm constitute what the Center for International Blood and Marrow Transplant Research defined as a very high-risk subset of a conventional high-risk class 3 group (here referred to as class 3 HR). We performed HSCT in 98 patients with related and unrelated donor stem cells. Seventy-six of the patients with age < 10 years received the more conventional myeloablative conditioning (MAC) regimen (cyclophosphamide, busulfan, ± fludarabine); the remaining 22 patients with age ≥ 10 years and hepatomegaly (class 3 HR), and in several instances additional comorbidity problems, underwent HSCT with a novel reduced-toxicity conditioning (RTC) regimen (fludarabine and busulfan). We then compared the outcomes between these 2 groups (MAC versus RTC). Event-free survival (86% versus 90%) and overall survival (95% versus 90%) were not significantly different between the respective groups; however, there was a higher incidence of serious treatment-related complications in the MAC group, and although we experienced 6 graft failures in the MAC group (8%), there were none in the RTC group. Based on these results, we suggest that (1) class 3 HR thalassemia patients can safely receive HSCT with our novel RTC regimen and achieve the same excellent outcome as low/standard-risk thalassemia patients who received the standard MAC regimen, and further, (2) that this novel RTC approach should be tested in the low/standard-risk patient population.

Combined Chelation Therapy with Daily Oral Deferiprone and Twice-Weekly Subcutaneous Infusion of Desferrioxamine in Children with β-Thalassemia: 3-Year Experience

Objective: To study the efficacy of combined treatment with oral and subcutaneous iron chelators. Material and Methods: 50-100 mg/kg/day of oral deferiprone (DFP) combined with 40 mg/kg/dose s.c. desferrioxamine (DFO) twice weekly were given to transfusion-dependent β-thalassemia children. Results: Enrolled patients (9 with β-thalassemia major and 33 with β-thalassemia hemoglobin E), ranging from 3 to 18 years in age, were divided into 3 groups; group 1 ferritin ≥1,000-2,500 ng/ml (n = 10), group 2 ferritin >2,500-4,000 ng/ml (n = 23) and group 3 ferritin >4,000 ng/ml (n = 9). Of the 42 patients, 28 reached the 36-month follow-up. Ten patients whose ferritin declined <15% while receiving 100 mg/kg/day of DFP were considered nonresponders. The median age and previous transfusion duration before enrollment were significantly higher in nonresponders than responders (p = 0.04 and 0.003, respectively). The responders exhibited a significant fall in median ferritin levels from 2,954.6 to 936.6 ng/ml (p < 0.001). Time to a significant decrease in serum ferritin among responders was 6 months. In 13 patients, 16 episodes of adverse events occurred: hemophagocytosis with cytopenia (n = 1), neutropenia (n = 2), thrombocytopenia (n = 2), elevated alanine aminotransferase (n = 5), elevated serum creatinine (n = 1), proteinuria (n = 1) and gastrointestinal discomfort (n = 4). Conclusion: Combination therapy with daily oral DFP and subcutaneous DFO twice weekly is a safe and effective alternative to chelation monotherapy in β-thalassemia children.

Comparative outcome of Thai pediatric osteosarcoma treated with two protocols: the role of high-dose methotrexate (HDMTX) in a single institute experience.

BACKGROUND High-dose methotrexate (HD-MTX) is recognized as an efficient component of therapy against pediatric osteosarcoma in combination with other drugs such as cisplatin (CDP), carboplatin (CBDCA), doxorubicin (ADM), etoposide (VP-16) and ifosfamide (IFO). OBJECTIVES To demonstrate the feasibility and effectiveness of the HD-MTX/CDP/DOX/VP-16/IFO [MTX(+)] protocol comparable to CDP/ADM/CBDCA/IFO [MTX(-)] for treating childhood osteosarcoma at Ramathibodi Hospital (1999-2014). MATERIALS AND METHODS A retrospective analysis was conducted of osteosarcoma patients aged less than 18 years treated with two chemotherapeutic regimens between 1999 and 2014. A total of 45 patients received the MTX(-) and 21 the MTX(+) protocol. RESULTS Overall limb-salvage and amputation rate were 12.9% and 77.7%, respectively. Kaplan- Meier analysis results for 3-year disease free survival (DFS) and overall survival (OS) regardless of treatment regimens were 43.4±6.0% and 53.2±6.1% respectively. The 3-year DFS and OS were improved significantly with the MTX(+) protocol compared to MTX(-) protocol (p=0.010 and p=0.009, log rank test) [69.8±10.5%, 79.8±9.1% for MTX(+) and 31.1±6.9%, 42.2±7.4% for MTX(-) protocol, respectively]. Patients with metastatic osteosarcoma treated with the MTX(+) protocol had statistically significant higher 3-year DFS and OS than those treated with the MTX(-) protocol (66.7±13.6% and 15.0±8.0% for 3-year DFS, p=0.010, 73.3±13.2% and 20±8.9% for 3-year OS, p=0.006, respectively). The independent risk factors for having inferior 3-year DFS and OS were poor histological response (tumor necrosis <90%) and treatment with the MTX(-) protocol. The multivariate analysis identified only the treatment with the MTX(-) protocol as an independent predictor of inferior OS with a hazard ratio (HR) of 3.53 (95% confidence interval of 1.2-10.41, p=0.022). CONCLUSIONS Our study demonstrated the tolerability, feasibility and efficacy of the HDMTX-based regimen improving the survival rate in pediatric osteosarcoma cases, in line with reports from developed countries.

Safety profile of a liquid formulation of deferiprone in young children with transfusion-induced iron overload: a 1-year experience

Background: Data on the use of deferiprone in young children with iron overload are limited. Objective: To study the safety profile of a liquid formulation of deferiprone in chelating young children with transfusion-induced iron overload. Patients and methods: A daily dose of 50–100 mg/kg BW in three divided doses of oral deferiprone was given to young patients who had received at least ten packed red cell transfusions and achieved a serum ferritin level >1000 μg/L during a 12-month period from 2011 to 2012. Results: Nine children (four males) diagnosed with various types of thalassaemia (n = 8) and hereditary spherocytosis (n = 1) were enrolled. Their mean (SD) age was 4.5 (1.9) years. The patients received 15–20 ml/kg BW of packed red cell transfusions every 4–8 weeks from a mean (SD) age of 2.1 (1.7) years to maintain a pre-transfusion haematocrit at 27%. A mean (SD) total of packed red cells of 5132 (2725) ml were given within a mean (SD) duration of 2.4 (1.1) years before the study. During the 1-year study period, they received a mean (SD) total of packed red cells of 2194 (680) ml or 138 (50) ml/kg BW with a mean (SD) daily iron load of 0.29 (0.12) mg/kg BW. The pre-treatment geometric mean of serum ferritin of 1863.8 μg/L decreased to 1279.7 μg/L after 1 year of treatment (P = 0.05). All patients tolerated the liquid formulation well and did not experience any gastro-intestinal discomfort, nausea or vomiting. Conclusion: The liquid formulation of deferiprone is safe in young children with transfusion-induced iron overload.BACKGROUND Data on the use of deferiprone in young children with iron overload are limited. OBJECTIVE To study the safety profile of a liquid formulation of deferiprone in chelating young children with transfusion-induced iron overload. PATIENTS AND METHODS A daily dose of 50-100 mg/kg BW in three divided doses of oral deferiprone was given to young patients who had received at least ten packed red cell transfusions and achieved a serum ferritin level >1000 μg/L during a 12-month period from 2011 to 2012. RESULTS Nine children (four males) diagnosed with various types of thalassaemia (n = 8) and hereditary spherocytosis (n = 1) were enrolled. Their mean (SD) age was 4.5 (1.9) years. The patients received 15-20 ml/kg BW of packed red cell transfusions every 4-8 weeks from a mean (SD) age of 2.1 (1.7) years to maintain a pre-transfusion haematocrit at 27%. A mean (SD) total of packed red cells of 5132 (2725) ml were given within a mean (SD) duration of 2.4 (1.1) years before the study. During the 1-year study period, they received a mean (SD) total of packed red cells of 2194 (680) ml or 138 (50) ml/kg BW with a mean (SD) daily iron load of 0.29 (0.12) mg/kg BW. The pre-treatment geometric mean of serum ferritin of 1863.8 μg/L decreased to 1279.7 μg/L after 1 year of treatment (P = 0.05). All patients tolerated the liquid formulation well and did not experience any gastro-intestinal discomfort, nausea or vomiting. CONCLUSION The liquid formulation of deferiprone is safe in young children with transfusion-induced iron overload.

Interphase-FISH screening for eight common rearrangements in pediatric B-cell precursor acute lymphoblastic leukemia.

This is the first pilot study to screen multiple common genetic aberrations in B‐cell precursor acute lymphoblastic leukemia (BCP‐ALL).

Intramuscular anti-D in chronic immune thrombocytopenia children with severe thrombocytopenia.

Nine patients with chronic immune thrombocytopenia and platelet counts <20 × 109/L, with a median age of 7.8 (3.8–15.5) years, received three phases of 10 mcg/kg/dose of intramuscular anti‐D. Phase 1 was anti‐D daily for 5 days, followed by phase 2, anti‐D weekly for 12 weeks and withheld when platelet counts ≥20 × 109/L, and then phase 3 was anti‐D once every 2 weeks for 24 weeks. According to the International Working Group criteria, in phase 1, 66.7% of patients responded to the treatment. In phases 2 and 3, 11.1% (0–41.7%) and 7.7% (0–33.3%) of total episodes of follow up, respectively, responded to the treatment. Therefore, intramuscular anti‐D given at a dose of 10 mcg/kg for 5 days is an alternative method to raise platelet counts in chronic immune thrombocytopenia children with severe thrombocytopenia where the intravenous form of anti‐D is not available.

Comparative outcomes of Thai children with acute lymphoblastic leukemia treated with two consecutive protocols: 11-year experience

Abstract The aim of this study was to determine outcomes and prognostic features of children with acute lymphoblastic leukemia (ALL) treated with two modified St Jude Childrens Research Hospital protocols at Ramathibodi Hospital (1997–2008). Event-free survival rates of the “previous protocol” were 88.3 ± 3.3% and 83.0 ± 3.9% and of the “current protocol” were 89.9 ± 3.4% and 88.0 ± 3.8%, at 3 and 5 years, respectively. Adverse prognostic features were identified only in the previous protocol study, including obesity, presenting leukocytes >100 × 109/L, high-risk group, persistent blasts in a day-15 marrow and sepsis. Sepsis also conferred inferior overall survival rates of patients in both protocols. Steady improvement in cure rate over the past decade has clearly demonstrated the optimal use of treatment protocols and a multidisciplinary approach to implementing pediatric cancer care in Ramathibodi Hospital. Our future challenges are refinement in risk and treatment stratification and reduction of treatment-related toxicities, prioritizing death from infections.

Preventable Severe Thalassemia among Children

Abstract This retrospective study analyzed 27 children with preventable severe thalassemia born to 24 at-risk couples between 1997 and 2017. The couples were categorized into two groups: the prenatal diagnosis (PND) group (n = 8) and the non PND group (n = 16). In the PND group, following comprehensive counseling on having a fetus with thalassemia, six couples decided to continue the pregnancy (n = 6). Termination of the two remaining fetuses was excluded as the thalassemia status was reported at a gestational age of 24 weeks. In the non PND group, medical errors were found in the misdiagnosis of couples as non thalassemia carriers (n = 4) and not offering PND to couples with known thalassemia carrier status when attending the antenatal clinic (ANC) (n = 2). Additionally, parental ignorance was found in parents experiencing their own thalassemia, or that of their spouse or child (n = 6). The remaining couples (n = 4) with known carrier status either directly refused PND or were ineligible for it. A total of five divorces (5/24 = 20.8%) occurred in the PND (n = 2) and the non PND (n = 3) groups. Knowledge, beliefs, religion, experience of thalassemia, as well as the sex of the at-risk fetus all influenced parental decisions. Therefore, both medical personnel and parents are key in preventing new cases of thalassemia. Parents should be aware of the consequences of having children with severe thalassemia, while medical personnel should provide accurate carrier detection and PND.