Michael Jeng

Relative response of patients with myelodysplastic syndromes and other transfusion-dependent anaemias to deferasirox (ICL670): a 1-yr prospective study

Objectives/methods:u2002 This 1‐yr prospective phase II trial evaluated the efficacy of deferasirox in regularly transfused patients aged 3–81u2003yrs with myelodysplastic syndromes (MDS; nu2003=u200347), Diamond–Blackfan anaemia (DBA; nu2003=u200330), other rare anaemias (nu2003=u200322) or β‐thalassaemia (nu2003=u200385). Dosage was determined by baseline liver iron concentration (LIC).

Prospective evaluation of patient-reported outcomes during treatment with deferasirox or deferoxamine for iron overload in patients with beta-thalassemia

BACKGROUNDnIron chelation therapy (ICT) with deferoxamine (DFO), the current standard for the treatment of iron overload in patients with transfusion-dependent disorders such as beta-thalassemia, requires regular subcutaneous or intravenous infusions. This can lead to reduced quality of life and poor adherence, resulting in increased morbidity and mortality in iron-overloaded patients with beta-thalassemia. Deferasirox is an orally administered iron chelator that has been approved for use in the United States, Switzerland, and other countries.nnnOBJECTIVEnThis analysis was conducted to compare patient-reported outcomes (PROs) during receipt of DFO infusions or once-daily oral therapy with deferasirox (ICL670).nnnMETHODSnPROs were prospectively evaluated as part of a randomized, Phase III study comparing the efficacy and safety profile of DFO 20 to 60 mg/kg per day with those of deferasirox 5 to 30 mg/kg per day in patients (age > or =2 years) with beta-thalassemia who were receiving regular transfusions and had a liver iron concentration of > or =2 mg/g dry weight. PRO questionnaires were completed by patients or a parent or legal guardian at baseline, week 4, week 24, and end of study (EOS). Patients assessed their level of satisfaction with study treatment (very satisfied, satisfied, neutral, dissatisfied, or very dissatisfied) and rated its convenience (very convenient, convenient, neutral, inconvenient, or very inconvenient). Time lost from normal activities due to ICT in the previous 4 weeks was recorded using a single global assessment. At week 4, patients who had previous experience with DFO were asked to indicate their preference for treatment (ICT received before the study, ICT received during the study, no preference, or no response) and the reason for that preference. At EOS, all patients were asked if they would be willing to continue using the ICT they had received during the study. All study analyses were performed in all patients who received at least 1 dose of study medication.nnnRESULTSnFive hundred eighty-six patients (304 females, 282 males; age range, 2-53 years) received treatment with DFO (n = 290) or deferasirox (n = 296). Significantly more patients treated with deferasirox reported being very satisfied or satisfied with treatment compared with those treated with DFO (week 4: 92.0% vs 50.4%, respectively; week 24: 89.6% vs 44.0%; EOS: 85.1% vs 38.7%; all, P < 0.001). At the same time points, the majority of those treated with deferasirox reported that treatment was very convenient or convenient compared with those treated with DFO (95.5% vs 21.3%, 91.7% vs 17.4%, and 92.7% vs 11.3%, respectively; all, P < 0.001). Among patients who had previously taken DFO and were randomized to receive deferasirox during the study, 96.9% reported a preference for deferasirox over DFO. At EOS, the proportion of patients indicating a willingness to continue study therapy was significantly greater in those receiving deferasirox than in those receiving DFO (85.8% vs 13.8%; P < 0.001).nnnCONCLUSIONSnIn this study, patient-reported satisfaction and convenience were significantly higher for the once-daily, oral ICT deferasirox than for DFO infusions. Among patients who had received DFO before the study, the majority indicated a preference for deferasirox over DFO. Most patients receiving deferasirox indicated that they would be willing to continue taking it. These results suggest that deferasirox had a positive impact on patients daily lives.

The role of vanin-1 and oxidative stress-related pathways in distinguishing acute and chronic pediatric ITP.

Pediatric immune thrombocytopenia (ITP) is usually self-limited. However, approximately 20% of children develop chronic ITP, which can be associated with significant morbidity because of long-term immunosuppression and splenectomy in refractory cases. To explore the molecular mechanism of chronic ITP compared with acute ITP, we studied 63 pediatric patients with ITP. Gene expression analysis of whole blood revealed distinct signatures for acute and chronic ITP. Oxidative stress-related pathways were among the most significant chronic ITP-associated pathways. Overexpression of VNN1, an oxidative stress sensor in epithelial cells, was most strongly associated with progression to chronic ITP. Studies of normal persons demonstrated VNN1 expression in a variety of blood cells. Exposure of blood mononuclear cells to oxidative stress inducers elicited dramatic up-regulation of VNN1 and down-regulation of PPARγ, indicating a role for VNN1 as a peripheral blood oxidative stress sensor. Assessment of redox state by tandem mass spectrometry demonstrated statistically significant lower glutathione ratios in patients with ITP versus healthy controls; lower glutathione ratios were also seen in untreated patients with ITP compared with recently treated patients. Our work demonstrates distinct patterns of gene expression in acute and chronic ITP and implicates oxidative stress pathways in the pathogenesis of chronic pediatric ITP.

Genomic analysis of bone marrow failure and myelodysplastic syndromes reveals phenotypic and diagnostic complexity

Accurate and timely diagnosis of inherited bone marrow failure and inherited myelodysplastic syndromes is essential to guide clinical management. Distinguishing inherited from acquired bone marrow failure/myelodysplastic syndrome poses a significant clinical challenge. At present, diagnostic genetic testing for inherited bone marrow failure/myelodysplastic syndrome is performed gene-by-gene, guided by clinical and laboratory evaluation. We hypothesized that standard clinically-directed genetic testing misses patients with cryptic or atypical presentations of inherited bone marrow failure/myelodysplastic syndrome. In order to screen simultaneously for mutations of all classes in bone marrow failure/myelodysplastic syndrome genes, we developed and validated a panel of 85 genes for targeted capture and multiplexed massively parallel sequencing. In patients with clinical diagnoses of Fanconi anemia, genomic analysis resolved subtype assignment, including those of patients with inconclusive complementation test results. Eight out of 71 patients with idiopathic bone marrow failure or myelodysplastic syndrome were found to harbor damaging germline mutations in GATA2, RUNX1, DKC1, or LIG4. All 8 of these patients lacked classical clinical stigmata or laboratory findings of these syndromes and only 4 had a family history suggestive of inherited disease. These results reflect the extensive genetic heterogeneity and phenotypic complexity of bone marrow failure/myelodysplastic syndrome phenotypes. This study supports the integration of broad unbiased genetic screening into the diagnostic workup of children and young adults with bone marrow failure and myelodysplastic syndromes.

Extranodal Rosai-Dorfman disease in children.

Sinus histiocytosis with massive lymphadenopathy (SHML), or Rosai-Dorfman disease (RDD), is a histiocytic disorder that usually presents with painless massive cervical lymphadenopathy. The course is usually self-limited, but treatment may be required in cases with compression of vital organs. Patients may present with extranodal involvement only, and in these cases the clinical and histologic diagnosis may be difficult. The authors describe three patients with RDD who had exclusive extranodal disease in the head and neck area, in whom the clinical presentation mimicked other more common conditions.

Chronic Transfusion Therapy for Children With Sickle Cell Disease and Recurrent Acute Chest Syndrome

The objective was to study the effects of chronic transfusion therapy (CTX) on the prevention of new episodes of acute chest syndrome (ACS) in children with sickle cell disease (SCD) and recurrent or unusually severe ACS. A retrospective chart review was performed of patients given CTX for recurrent or severe ACS. Frequency, median severity score, and median hospital stay for ACS episodes were determined. Differences in these values before and during CTX were analyzed. Twenty-seven patients were identified. Before treatment, the ACS incidence was 1.3 episodes per patient-year; during treatment, it decreased to 0.1 episodes per patient-year (P < 0.0001). The median severity score for ACS episodes was 0.8 (range 0-5) before CTX and 0.5 (0-3) during CTX (P = 0.84). The median hospital stay was 5 days (range 3-15 days) before CTX and 3 days (2-7 days) during CTX (P = 0.38). CTX significantly reduces the incidence of ACS events among patients with a history of recurrent or severe episodes but does not significantly decrease their severity. The effectiveness of CTX should be prospectively compared with that of hydroxyurea and stem cell transplantation.

Precursor B-cell acute lymphoblastic leukemia presenting with hemophagocytic lymphohistiocytosis

Hemophagocytic lymphohistiocytosis (HLH) is a hyperinflammatory syndrome which can be an inherited congenital disorder or can develop secondary to malignancy, infection, or autoimmune disease. Secondary HLH due to malignancy occurs most commonly with T or NK‐cell lymphoid neoplasms. HLH with B‐cell malignancies is less common and HLH has rarely been described in association with precursor B‐cell acute lymphoblastic leukemia (B‐ALL). We report three cases of HLH associated with B‐ALL and review 17 cases of ALL‐associated HLH previously reported in the literature. Pediatr Blood Cancer 2008;50:381–383.

ITRACONAZOLE-ENHANCED VINCRISTINE NEUROTOXICITY IN A CHILD WITH ACUTE LYMPHOBLASTIC LEUKEMIA

A boy with acute lymphoblastic leukemia (ALL) experienced life-threatening vincristine neurotoxicity while simultaneously exposed to itraconazole. Five pediatric and six adult cases of itraconazole-enhanced vincristine toxicity have been reported, all with ALL. Upon cessation of the itraconazole, the patients symptoms resolved, which is similar to the outcome of the previously reported cases: 10 of 11 patients had complete resolution of symptoms.

Epstein-Barr virus-associated peripheral T-cell lymphoma and hemophagocytic syndrome arising after liver transplantation: case report and review of the literature.

Post‐transplantation lymphoproliferative disorders (PTLD) are a well‐recognized complication of solid organ transplantation. The vast majority of PTLD are Epstein–Barr virus (EBV)‐related infections that manifest as B‐cell malignancies. We report an unusual case of an EBV‐associated T‐cell lymphoma in a 10‐year‐old boy who had previously undergone liver transplantation at age 4 years. He presented with hemophagocytic syndrome (HPS) and active EBV infection, with positive serum titers and polymerase chain reaction (PCR) for EBV in blood, colon, and antral samples.

Natural history of moderate aplastic anemia in children

Moderate aplastic anemia (MAA) in children is a rare, idiopathic condition of bone marrow insufficiency that can resolve spontaneously, persist for months or years, or progress to severe aplastic anemia (SAA). We evaluated the rate of progression to SAA.