Shih-Hsiang Chen

Cooperating gene mutations in childhood acute myeloid leukemia with special reference on mutations of ASXL1, TET2, IDH1, IDH2, and DNMT3A

Gene mutations involving epigenetic regulators recently have been described in adult acute myeloid leukemia (AML). Similar studies are limited in children. We analyzed gene mutations and cooperation in pediatric AML with special reference on mutated epigenetic regulators. Nineteen gene mutations, including 8 class I genes, 4 class II genes, WT1 and TP53 (class III), and 5 epigenetic regulator genes (class IV), were analyzed in 206 children with de novo AML. Mutational analysis was performed with polymerase chain reaction-based assay followed by direct sequencing. One hundred seventeen of 206 patients (56.8%) had at least one mutation: 51% class I, 13% class II, 6.8% class III, and 5.6% class IV. FLT3-internal tandem duplication was most frequent, and 29% of patients had more than one gene mutation. Two patients carried ASXL1 mutations, both with t(8;21), 2 had DNMT3A mutations, 2 had IDH1 mutations, 1 had IDH2 mutation, and 3 had TET2 mutations. Both patients with IDH1 mutations had AML-M0 subtype and MLL-partial tandem duplication. Cooperating mutations with mutated epigenetic regulators were observed in 8 of 10 patients. We conclude that mutated epigenetic regulators were much less than those in adult AML but with frequent cooperating mutations. ASXL1, TET2, and IDH1 mutations were associated with specific genetic subtypes.

Unrelated cord blood transplantation for thalassaemia: a single-institution experience of 35 patients

Our study was designed to prospectively determine whether or not unrelated cord blood transplantation (CBT) can produce outcomes comparable to related donor transplantation for children with β-thalassaemia. In 35 patients, 40 transplants were performed between October 2003 and September 2009. HLA matching at enrolment was 6/6 (n=8), 5/6 (n=16), 4/6 (n=27), or 3/6 (n=1) by low-resolution HLA-A, -B, and high-resolution DRB1. These patients received non-manipulated grafts without ex vivo expansion or T-cell depletion. The median number of nucleated and CD34+ cells infused was 7.8 × 107/kg (range, 2.8–14.7 × 107/kg) and 4.0 × 105/kg (range, 1.7–19.9 × 105/kg), respectively. The 5-year OS and thalassaemia-free survival after the first transplant were 88.3 and 73.9%, respectively. The cumulative incidence of TRM at 2 years was 11.7%. Fourteen patients developed chronic skin GVHD. Thirty patients were alive and transfusion-independent with a Lansky performance score ⩾80% achieved between 6 and 76 months post transplant (median, 36 months). These data compare acceptably with the survival rates of related-donor BMT for thalassaemia and suggest that patients without an available HLA-compatible sibling but who have well-matched unrelated donors should also be considered for CBT.

Transplantation of unrelated donor umbilical cord blood utilizing double-unit grafts for five teenagers with transfusion-dependent thalassemia

To augment graft cell dose, we evaluated the safety of the combined transplantation of two partially HLA-matched umbilical cord blood (UCB) units. Five patients with transfusion-dependent thalassemia, median age 11.1 years (range 10–13.1), received 2 UCB units after myeloablative conditioning. Cord blood units were a 4/6-HLA-match or better with the recipient, and contained a minimum combined pre-freeze CD34 cell dose of 3.0 × 105/kg. All patients engrafted at a median of 15 days (range 12–19). Four patients with durable trilineage engraftment showed acute grade I–III GVHD; none developed extensive chronic GVHD until the date of last contact. The median times to red blood cell transfusion independence and platelet engraftment were 32 and 49 days after transplant, respectively. With a median follow-up of 18.5 months (range 11–32), four patients transplanted with UCB from two different partially HLA-matched donors were transfusion-independent. Therefore, transfusion of two partially HLA-matched UCB units is safe, and may overcome the cell-dose barrier that limits the use of UCB in long-term recipients of multiple transfusions for thalassemia.

Transplantation of Unrelated Donor Umbilical Cord Blood for Nonmalignant Diseases: a Single Institution's Experience with 45 Patients

The potential benefits of unrelated donor bone marrow transplantation are offset by the immunologic complications of graft-versus-host disease (GVHD) and infection. We used cryopreserved umbilical cord blood (UCB) as a strategy to reduce the risks of GVHD and treatment-related mortality (TRM) and improved survival. Data on 45 patients with median age of 4.5 years who received transplants between October 2003 and February 2009 for the treatment of nonmalignant diseases were evaluated. As of May 15, 2009, the median follow-up was 25 months (range: 3-66). The majority (82%) of patients received an HLA-mismatched graft. The median infused total nucleated cell dose was 7.6 x 10(7)/kg and CD34(+) count 4.0 x 10(5)/kg. Primary graft failure was encountered after 4 transplantations (8%). Log-rank tests and Cox regression analyses were used to determine the effects of various demographic, graft-related, and treatment factors on engraftment, GVHD, TRM, graft failure, and survival. Incidences of neutrophil and platelet engraftment were 88% and 82%, respectively. The incidence of severe grade III-IV acute GVHD (aGVHD) was 42%. Five-year overall survival (OS) and disease-free survival (DFS) were 88.1% and 77.1%, respectively. The cumulative incidence of TRM at 2 years was 12.0%. When cell dose and other factors are optimal, unrelated CBT is a promising approach for curative therapy of nonmalignant diseases.

Clinical aspects, immunologic assessment, and genetic analysis in Taiwanese children with hemophagocytic lymphohistiocytosis.

Background: Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening syndrome characterized by immune disturbance associated with certain genetic defects. This study aimed to define the clinical spectrum, immunology, and candidate genes in HLH in Taiwanese patients. Patients and Methods: The medical records of children who met the updated diagnostic criteria and had confirmed hemophagocytosis by bone marrow aspiration between 1992 and 2007 were retrospectively evaluated. The clinical course and prognosis were analyzed. Quantitative immunoglobulin, lymphocyte subsets, cytotoxicity to K562 cells, intracellular natural killer perforin expression, and candidate genes including SH2D1A, PFR1, Mun13-4, and STX11 genes were also investigated. Results: Thirty-two patients (16 male) were evaluated during the 15-year period. The underlying diseases were acute lymphoblastic leukemia, systemic lupus erythematosus, natural killer malignancy, juvenile idiopathic arthritis, and Chediak-Higashi syndrome. Epstein-Barr virus (EBV)-associated HLH was present in 12 patients, 6 of whom died, while 12 of 20 non–EBV-associated patients died despite aggressive polychemotherapy. Extreme immunoglobulin values occurred in 3 fatal cases. There was decreasing percentage of CD4+, CD16+56+, and B-memory cells and increasing CD8+, activated lymphocyte, and T-memory cells among the patients. Cytotoxicity in 14 patients and intracellular perforin expression in 13 were diminished but restored to borderline normal range during the convalescent stage. None of the mutations of SH2D1A, PFR1, Mun13-4, and STX11 genes were found. Conclusions: In the treatment of Taiwanese HLH patients, aggressive chemotherapy in EBV-associated patients and stem cell transplantation in non–EBV-associated patients are recommended to improve survival. Individualized immune dysregulation instead of the well-known candidate genetic mutations can explain the genetic variation in our cohort.

Clinical Features and Genetic Analysis of Taiwanese Patients With the Hyper Igm Syndrome Phenotype

Objectives: Hyper IgM syndrome (HIGM), characterized by recurrent infections, low serum IgG and IgA, normal or elevated IgM, defective class switch recombination and somatic hypermutation, are heterogeneous disorders with at least 6 distinct molecular defects, including the CD40 ligand (CD40L) and the nuclear factor &kgr;B essential modulator (NEMO, also known as IKK&ggr;) genes (both X-linked), the CD40, activation-induced cytidine deaminase (AICDA or AID), uracil-DNA glycosylase genes (autosomal recessive) and I&kgr;B&agr; (IKBA) (autosomal dominant). Our objective was to determine the molecular basis and clinical features of Taiwanese patients with the HIGM phenotype. Methods: Clinical manifestations and candidate genes were analyzed in a nationwide population-based study. Results: Among 14 patients (12 unrelated families) since 2003, 10 patents were identified (8 families) with CD40L mutations, including 2 novel deletions of “A” nucleotide (Del 347A and Del 366A), both frameshift and stop at the 127th location; 1 novel AID deletion mutation lack of the 37thAsp and 38th Ser; 1 ataxia–telangiectasia mutation; and 1 deletion of chromosome 1q42. An adult-onset patient with mutant (Thr254Met)CD40L had approximately 30% detectable affinity and therefore less severity. Memory B cells decreased in patients with CD40L and activation-induced cytidine deaminase mutations. Three mortalities encompassed renal cell carcinoma in 1 patient with (Tyr169Asn)CD40L, pneumothorax in 1 with (Tyr140Stop)CD40L and pneumonia after chemotherapy in an ataxia–telangiectasia patient. One patient without detectable genetic defects but normal lymphocyte proliferation resembled the mild form of common variable immune deficiency phenotype. Conclusions: In contrast to those with AICDA mutation, small chromosome 1 q42 deletion and unknown genetic defect, the majority (10/14; 71.4%) with CD40L mutations except (Thr254Met) and an ataxia–telangiectasia patient had the severe form of HIGM phenotype.

Successful unrelated mismatched cord blood transplantation in a child with malignant infantile osteopetrosis

Abstract:  Allogeneic hematopoietic stem cell transplantation represents the only curative option for malignant infantile osteopetrosis (MIOP), a rare disease of infants and young children, characterized by excessive accumulation of mineralized bone and abnormal hematopoiesis. We report a case of successful engraftment and stable full‐donor chimerism in a patient with MIOP who underwent unrelated donor cord blood transplantation (CBT). The donor was 2‐loci human leukocyte antigen (HLA)‐mismatch. After a conditioning regimen based on the combination of busulfan, cyclophosphamide, total body irradiation, and antithymocyte globulin, the patient received a dose of 3.85 × 107/kg of nucleated cells. Neutrophil and platelet engraftment had been achieved by day +33 and +82, respectively, and the patient was discharged home on day +89. A successful engraftment of donor hematopoiesis was demonstrated and the child experienced grade II acute graft‐vs.‐host disease (GVHD) involving the skin only. A remarkable but non‐progressive decrease in lumbar spine bone mineral density was observed in the first nine months post‐transplant. This case suggests that unrelated donor CBT may be a feasible option in case of unavailability of a fully HLA‐matched related or unrelated donor.

“Do-not-resuscitate” orders in patients with cancer at a children’s hospital in Taiwan

Objectives: To quantify the use of do-not-resuscitate (DNR) orders in a tertiary-care children’s hospital and to characterise the circumstances in which such orders are written. Design: Retrospective study conducted in a 500-bed children’s hospital in Taiwan. Patients: The course of 101 patients who died between January 2002 and December 2005 was reviewed. The following data were collected: age at death, gender, disease and its status, place of death and survival. There were 59 males and 42 females with a median age of 103 months (range 1–263 months). 50 children had leukaemias, and 51 had malignancies other than leukaemia. The t test and the χ2 test were applied as appropriate. Results: The study found that 44% of patient deaths occurred in the paediatric oncology ward; 29% of patient deaths occurred in the intensive care unit; and 28% of patients died in their home or at another hospital. Other findings included the following: 46 of 101 (46%) patients died after attempted cardiopulmonary resuscitation and 55 (54%) died with a DNR order in effect. The mean age at death was 9.8 years in both groups with or without DNR orders. Conclusions: From the study of patient deaths in this tertiary-care children’s hospital, it was concluded that an explicit DNR order is now the rule rather than the exception, with more DNR orders being written for patients who have been ill longer, who have solid tumours, who are not in remission and who are in the ward.

Primary intraspinal mesenchymal chondrosarcoma: report of one case.

We report a case of primary intraspinal mesenchymal chondrosarcoma in an 11-year-old boy. Contrast-enhanced MRI revealed a hyperintense, sausage-shaped mass extending from C7 to T2. The lesion located anterolaterally on the left side, pushing the spinal cord to the right and posterior. Microscopic examination and immunohistochemical studies confirmed the diagnosis of mesenchymal chondrosarcoma. Follow-up studies have shown no tumor recurrence for 2 years. This tumor is rare but should be considered for differential diagnosis in spinal tumors.

Early transplantation of unrelated cord blood in a two-month-old infant with Wiskott-Aldrich syndrome.

Abstract:  This report exemplified a success of unrelated CBT in a two‐month‐old boy with Wiskott–Aldrich Syndrome. Umbilical cord blood was chosen as the stem‐cell source because of its immediate availability and reduced tendency to cause GVHD. The conditioning regimen was cyclophosphamide, busulfan, and antithymocyte globulin. GVHD prophylaxis consisted of cyclosporin and methylprednisolone. The patient received an HLA 1‐locus‐mismatched cord blood unit, and the total number of infused nucleated cells was 11.14 × 107/kg. Neutrophil engraftment was achieved on day +11, and a platelet count greater than 50 × 109/L was achieved on day +71. He is currently alive and doing well at nine months post‐transplant and free of any bleeding episodes. This case suggests that unrelated donor CBT may be safe and technically feasible, even in early infancy, when an appropriately matched related or unrelated donor is unavailable.