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Mitchell S Cairo

Publications and source records attributed to Mitchell S Cairo.

At least 37 records · Page 2Linked to original sources

Childhood and adolescent non-Hodgkin lymphoma: new insights in biology and critical challenges for the future.

Pediatric non-Hodgkin lymphoma (NHL) is a common and fascinating group of diseases with distinctive underlying genetic events that characterize the major histologic subtypes: diffuse large B-cell lymphoma, Burkitt lymphoma, anaplastic large cell lymphoma and lymphoblastic lymphoma. With systematic improvements in therapy over recent decades, the vast majority of children with NHL of all subtypes are now cured. The similarities and differences between adult and childhood presentations of disease, and whether or not some subtypes of NHL and leukemia are the same or different disease entities, are interesting questions that will be addressed with advances in our understanding of the molecular and genetic bases of these diseases. As is the case with other pediatric malignancies, growing emphasis is now being placed on the development of less toxic, targeted therapeutic approaches, and this review highlights some of the biological discoveries that will potentially open these avenues.

Adolescent↗

Reduced-intensity allogeneic stem cell transplantation in adults and children with malignant and nonmalignant diseases: end of the beginning and future challenges.

During the last 10 years, multiple studies using reduced-intensity (RI) conditioning followed by allogeneic stem cell transplantation (AlloSCT) have been reported in adult and, less so, pediatric recipients. RI AlloSCT allegedly eradicates malignant cells through a graft-versus-leukemia/graft-versus-tumor effect provided by alloreactive donor T lymphocytes, natural killer cells, or both. Various studies have clearly demonstrated a graft-versus-leukemia/graft-versus-tumor effect in hematologic malignancies and solid tumors. Acute short-term toxicity, including infection and organ decompensation after myeloablative conditioning therapy, can result in a significant incidence of early transplant-related mortality. More importantly, long-term late effects-including growth retardation, infertility, and secondary malignancies-are major complications after myeloablative conditioning therapy, especially in vulnerable children, who are more susceptible to these complications. Recent results comparing RI conditioning with myeloablative conditioning followed by HLA-matched sibling AlloSCT have demonstrated a significant reduction in use of blood products, risk of infections, transplant-related mortality, length of hospitalization, and feasibility of conditioning therapy in outpatient settings. Despite the success of RI AlloSCT, large prospective randomized multicenter studies are necessary to define the appropriate patient population, optimal conditioning regimens and pretransplantation immunosuppression, role of donor lymphocyte infusions, duration of hospitalization, overall survival, cost-benefit ratio, and differences in long-term effects to evaluate the role of RI AlloSCT more fully. We review the recent experience of RI AlloSCT in adults and children with both malignant and nonmalignant diseases and discuss the challenges for the future.

Adult↗

Increased induction of allogeneic-specific cord blood CD4+CD25+ regulatory T (Treg) cells: a comparative study of naïve and antigenic-specific cord blood Treg cells.

OBJECTIVE: The genetic and immunological mechanism(s) responsible for the significant decrease in the incidence of graft-vs-host disease (GVHD) following HLA-disparate unrelated cord blood transplantation remains largely unknown. In this study, we investigated if cord blood (CB) CD4(+)CD25(+) T cells play a significant role in reducing the immune responses of allo-reactive CD4(+)CD25(-) T lymphocytes. METHODS: We compared CB CD4(+)CD25(-) and CD4(+)CD25(+) T cells, either naïve or antigenic stimulated, to their counterparts in unmobilized adult peripheral blood (APB) with respect to genetic expression patterns, immunophenotype, suppressive activity, and mechanism(s) of suppression. RESULTS: Both naïve CB and APB CD4(+)CD25(+) T cells expressed similarly elevated mRNA levels of CTLA-4, GITR, Foxp3, CD25, and elevated protein levels of CTLA-4 (p < 0.001) and GITR (p < 0.001). However, only naïve APB but not CB CD4(+)CD25(+) T cells showed suppression of allogeneic responses. Stimulation of CD4(+)CD25(-) T cells by MUTZ-iDC (MUTZ-3-specific immature dendritic cells) elicited amplification of these genes and potent suppression (69% +/- 5% and 71% +/- 3% suppression, p < 0.001, CB and APB, respectively) on CD4(+)CD25(-) T cell proliferation induced by MUTZ-iDC but not by unrelated stimulators. Compared to that from unmobilized APB, a significantly higher percentage (2.7-fold +/- 0.5-fold; p < 0.002) of CD4(+)CD25(+)CTLA-4(+) T regulatory (Treg) cell subsets were induced from CB CD4(+)CD25(-) T cells following allogeneic stimulation. CONCLUSION: Our results suggest that CB CD4(+)CD25(+) Treg cells, which are induced at a higher rate by allogeneic stimulation when compared to unmobilized APB, can readily function as potent allogeneic immune suppressors and may in part contribute to the decrease in CB alloantigen recognition and activation of CB CD4(+)CD25(-) T cells.

Antigen Presentation↗

Phase I/II dose escalation study of recombinant human interleukin-11 following ifosfamide, carboplatin and etoposide in children, adolescents and young adults with solid tumours or lymphoma: a clinical, haematological and biological study.

Thrombocytopenia remains the major dose-limiting toxicity of myelosuppressive chemotherapy in children with solid tumours. Recombinant human interleukin-11 (rhIL-11) has been approved by the Food and Drug Administration as treatment for adults with solid tumours and lymphomas with severe chemotherapy-induced thrombocytopenia. We conducted a phase I/II trial of rhIL-11 following ifosfamide, carboplatin and etoposide (ICE) chemotherapy in children with solid tumours or lymphomas. Patients received ifosfamide 1800 mg/m(2)/d for 5 d, carboplatin 400 mg/m(2)/d for 2 d and etoposide 100 mg/m(2)/d for 5 d with rhIL-11 subcutaneous (s.c.) at 25-125 microg/kg/d on days 6-33. Forty-seven patients with median age 10.5 years (range, 0.7-26 years) were studied. Median days to absolute neutrophil count >/=0.5 x 10(9)/l, platelet count >/=50 x 10(9)/l and platelet transfusions were 23, 18, 18, 16.5 and 18.5, 21, 20, 18 and 3, 3, 4, and 2 d at doses 25, 50, 75 and 100 Schulteg/kg respectively. There was a dose-dependent increase in C(max) (7.6-25.5 ng/ml), AUC(0-rho) (57-209 ng.h/ml) and T(1/2) (4-8.2 h) respectively. There was a 4% incidence of anti-IL-11 antibody formation. Clinically important adverse events to rhIL-11 were papilloedema and periosteal bone formation. In summary, rhIL-11 was well tolerated at doses of </=50 microg/kg (maximal tolerated dose) and associated with improved haematological recovery and reduced platelet transfusion requirements compared with historical controls receiving similar ICE chemotherapy without rhIL-11.

Adolescent↗

Immaturity of IL-18 gene expression and protein production in cord blood (CB) versus peripheral blood (PB) mononuclear cells and differential effects in natural killer (NK) cell development and function.

We have previously demonstrated dysregulation of IL-12 and IL-15 gene and protein expression between activated cord blood (CB) versus peripheral blood (PB) mononuclear cells (MNCs). In the present study, we compared IL-18 gene expression and protein production and IL-18 mRNA half-life in basal versus activated CB versus PB MNCs, the effects of IL-18 +/- IL-12 on MNCs IFN-gamma protein production and ex vivo expansion and activation of CB with IL-12 + IL-2 + anti-CD3 +/- IL-18. Basal and activated levels of IL-18 were significantly higher in PB versus CB MNCs (P < 0.05). IL-18 mRNA was coincidental with protein levels and significantly lower in CB (P < 0.05) and its half-life significantly shorter in CB versus PB MNCs (P < 0.05). IL-18 synergistically with IL-12 induced IFN-gamma production from PB greater than CB MNCs (P < 0.05). NK cells expansion (P < 0.001) and cytotoxicity (P < 0.01) was significantly increased with IL-12 + IL-2 + anti-CD3 and IL-18. In summary IL-18 gene expression and protein production are significantly decreased in activated CB versus PB MNCs, in part secondary to increased degradation of CB IL-18 mRNA. These results may have implications for the mechanism(s) in part responsible for the immaturity of CB T-cell immunity.

Apoptosis↗

Childhood anaplastic large cell lymphoma has a high incidence of ALK gene rearrangement as determined by immunohistochemical staining and fluorescent in situ hybridisation: a genetic and pathological correlation.

Anaplastic large cell lymphoma (ALCL) comprises 10-15% of childhood non-Hodgkin lymphomas (NHL). Systemic ALCL is highly associated with anaplastic lymphoma kinase (ALK) gene translocations with over-expression of ALK protein. We studied ALK rearrangements using fluorescence in situ hybridisation (FISH) and ALK immunohistochemical staining in 43 paediatric systemic ALCLs. FISH (performed on 35 cases) identified a translocation in 29 cases (83%). Immunohistochemistry identified ALK over-expression in 42/43 cases (97%) with the single ALK-negative case demonstrating an ALK rearrangement by FISH, indicating 100% incidence of ALK translocations.

Adolescent↗

Results of the cord blood transplantation (COBLT) study unrelated donor banking program.

BACKGROUND: The goals of the Cord Blood Transplantation (COBLT) Study banking program initiated in 1996 were to develop standard operating procedures (SOPs) for cord blood (CB) donor recruitment and banking and to build an ethnically diverse unrelated CB bank to support a transplantation protocol. STUDY DESIGN AND METHODS: The program included collection centers, three banks, a steering committee, and a medical coordinating center (MCC) that developed and validated SOPs and a Web-based data collection system. External oversight was performed by the National Heart, Lung, and Blood Institute and the MCC. RESULTS: A total of 34,799 potential donors were screened and 20,710 consented. A total of 17,207 ethnically diverse units were collected between 1998 and 2001. A total of 11,077 (64%) units were cryopreserved and quarantined. Of these, 79 percent met eligibility criteria and were HLA-typed and entered into the search registry. Higher CB volumes and cell counts were obtained from cesarean sections compared to vaginal deliveries. Units from African American persons contained lower cell counts per volume compared to other ethnicities. Birth weight correlated with volume and cell content. External oversight was accomplished through custom reports generated by the data collection system and periodic site visits. During maintenance, a breach in the SOPs was detected during a site visit at one of the banks. These units were designated for future use in nonclinical research. CONCLUSION: The COBLT Study demonstrated that SOPs and data collection can be implemented in multiple banks coordinated by one MCC. Relationships between donor demographics and CB content may be useful in the development of other CB banking programs.

Blood Banks↗

Characterization of banked umbilical cord blood hematopoietic progenitor cells and lymphocyte subsets and correlation with ethnicity, birth weight, sex, and type of delivery: a Cord Blood Transplantation (COBLT) Study report.

BACKGROUND: The Cord Blood Transplantation (COBLT) Study banking program was initiated in 1996. The study goals were to develop standard operating procedures for cord blood (CB) donor recruitment and banking and to build an ethnically diverse unrelated CB bank to support a transplantation protocol. STUDY DESIGN AND METHODS: The hematopoietic progenitor cell (HPC) and lymphocyte subset (LS) content of approximately 8000 CB units were characterized, and these results were correlated with donor ethnicity, birth weight, gestational age, sex, and type of delivery. RESULTS: There was a significant correlation of CD34+ cell count with colony-forming unit (CFU)-granulocyte-macrophage (r=0.68, p<0.001), CFU-granulocyte-erythroid-macrophage-megakaryocyte (r=0.52, p<0.001), burst-forming unit-erythroid (BFU-E; r=0.61, p<0.001), and total CFUs (r=0.67, p<0.001). Nucleated red blood cell count was significantly correlated with total CD34+ (r=0.56, p<0.001), total CFU (r=0.50, p<0.001), BFU-E (r=0.48, p<0.001), and counts of CD34+ subsets (p<0.001). Caucasian ethnicity was significantly correlated with higher CD3+/CD4+, CD19+, and CD16+/CD56+ LSs. Furthermore, CD34+/CD38- and CD34+/CD61+ CB units (HPC-C) were significantly lower in African American and Asian persons compared to Caucasian and Hispanic persons. Male sex was associated with significantly fewer CD3+/CD4+, CD19+, and CD16+/CD56+ but increased CD3+/CD8+ LSs (p<0.001). Finally, cesarean section was associated with significantly higher total CFU and CD16+/CD56+ but lower CD3+/CD4+, CD3+/CD8+, and CD19+ LSs. CONCLUSION: These results provide a standard and range for uniformly processed HPC-C progenitor cells and LSs. CB progenitor cells and/or LSs may in the future predict for rapidity of engraftment, incidence of graft-versus-host disease, speed and quality of immunore- constitution, graft-versus-tumor effects, and/or success of gene transfection after CB transplantation.

Antigens, CD34↗

Dysregulation of expression of immunoregulatory and cytokine genes and its association with the immaturity in neonatal phagocytic and cellular immunity.

BACKGROUND: Innate and adaptive immunity is comprised of cellular and humoral factors that provide rapid protection against microbial invasion. However, immaturity of innate and adaptive immune responses in the perinatal period predisposes the neonate to increased infectious morbidity and mortality from a variety of organisms. OBJECTIVES: To elucidate dysregulation of expression of various immunoregulatory and cytokine genes and its association with the immaturity in neonatal phagocytic cellular immunity. METHODS: Comparison of protein production and mRNA of granulocyte macrophage colony-stimulating factor (GM-CSF), macrophage colony-stimulating factor (M-CSF), granulocyte colony-stimulating factor (G-CSF), interleukin (IL)-12, IL-15 and IL-18 in adult peripheral blood (APB) mononuclear cells (MNC) and cord blood (CB) MNC was studied. Effects of hematopoietic growth factors (HGFs, GM-CSF, M-CSF, G-CSF, IL-11) were studied in vivo in rats as well as randomized controlled studies conducted in neonates. Oligonucleotide microarrays were used to study gene expression patterns of activated CB and APB monocytes and dendritic cells. RESULTS AND CONCLUSIONS: We demonstrated dysregulation of various immunoregulatory and cytokine genes in CB MNC. This dysregulation may in part explain the immaturity of neonatal cell-mediated immunity. There are probably various dysregulated cytokines yet to be discovered. Biological agents such as IL-2, IL-12, IL-11 and/or IL-18 alone or in combination with HGFs should be considered for future studies to identify new approaches to enhance neonatal host defense, and thereby decrease the incidence of neonatal sepsis and the consequent high risk of morbidity and mortality.

Animals↗

TCL1 expression and Epstein-Barr virus status in pediatric Burkitt lymphoma.

Elevated T-cell leukemia-1 (TCL1) oncoprotein expression might promote human Burkitt lymphoma (BL) because increased TCL1 causes Burkitt-like lymphomas in TCL1 transgenic mice. Epstein-Barr virus (EBV) infection has been implicated as a cause of increased TCL1 expression in multiple BL cell lines, suggesting a critical connection between EBV and TCL1-induced BL. The TCL1 expression and EBV status of 14 sporadic pediatric BL cases was determined by immunohistochemical staining for TCL1 and in situ hybridization for EBV-encoded RNA (EBER). Our results showed TCL1 protein in 11 cases, predominantly in the nucleus with strong-intensity staining. EBER was positive in 4 cases, with 3 of these cases also TCL1+. In the 10 cases that were EBER-, TCL1 was strongly positive in 8. These data indicate that the TCL1 oncoprotein is expressed strongly in most pediatric BL cases. However, persistent EBV is not essential for increased TCL1 expression, although elevated TCL1 and c-MYC coexpression might cooperate in the development of most pediatric and adult BL cases.

Adolescent↗

Rasburicase: a new approach for preventing and/or treating tumor lysis syndrome.

Tumor lysis syndrome (TLS) is an oncologic emergency requiring prompt attention to the management of potentially life-threatening metabolic derangements. Hyperuricaemia is one of the prominent features of TLS which, if not adequately prevented or treated, may lead to renal failure, requiring dialysis. Conventional management of hyperuricaemia involved the use of aggressive hydration, urinary alkalinization and allopurinol. Despite these measures, as many as 14.1% of high-risk patients may still develop renal failure. With the advent of newer agents such as rasburicase, the paradigm of TLS management has shifted towards risk stratification and the use of rasburicase in conjunction with hydration in patients at high risk for TLS. The advantage of rasburicase over allopurinol is its rapid onset of action, lack of need for urine alkalinization, which may worsen hyperphosphataemia and a satisfactory safety profile. Overall, rasburicase offers a safe and more effective alternative to allopurinol in patients at highest risk for TLS. Some of the unanswered questions requiring further investigation with regard to rasburicase use include the optimal number of doses needed, optimal dose based on uric acid levels and tumor burden, dosing in obese patients and maximum dose.

Clinical Trials as Topic↗

Tumor lysis syndrome: pathophysiology, definition, and alternative treatment approaches.

Tumor lysis syndrome (TLS), a life threatening metabolic syndrome seen in malignancies with high tumor burden, is reviewed in this article. The new Cairo and Bishop classification system is discussed as well as the clinical management of this syndrome. Special emphasis is placed on the use of a relatively new agent, rasburicase, as an alternative to allopurinol in the management of TLS-associated hyperuricemia.

Diagnosis, Differential↗

Myeloablative allogeneic hematopoietic stem cell transplantation in patients who experience relapse after autologous stem cell transplantation for lymphoma: a report of the International Bone Marrow Transplant Registry.

Myeloablative allogeneic hematopoietic stem cell transplantation (allo-HSCT) is increasingly used in patients with lymphoma who experience disease relapse after autologous hematopoietic stem cell transplantation (auto-HSCT) because the allograft is tumor free and may induce a graft-versus-tumor effect. We analyzed 114 patients treated with this approach from 1990 to 1999 to assess disease progression, progression-free survival (PFS), and overall survival (OS). Cumulative incidence of disease progression at 3 years was 52%, whereas treatment-related mortality was 22%, lower than previously reported. Three-year probabilities of OS and PFS were 33% and 25%, respectively. With prolonged follow-up, however, nearly all patients experienced disease progression, and 5-year probabilities were 24% and 5%, respectively. Complete remission at the time of allo-HSCT and use of total body irradiation (TBI) in patients with non-Hodgkin lymphoma (NHL) were associated with lower rates of disease progression and higher rates of OS. In summary, allo-HSCT is feasible for patients with lymphoma who have relapses after auto-HSCT and can result in prolonged survival for some, but it is usually not curative. Most likely to benefit are patients who have HLA-matched sibling donors, are in remission, and have good performance status.

Adolescent↗

Differential gene expression patterns by oligonucleotide microarray of basal versus lipopolysaccharide-activated monocytes from cord blood versus adult peripheral blood.

Monocytes (Mo) are critically important in the generation of inflammatory mediators, cytokines/chemokines, and regulation of innate and adaptive immune responses. We and others have previously demonstrated significant dysregulated cytokine gene expression and protein production and in vitro functional activities of activated cord blood (CB) vs adult peripheral blood (APB) mononuclear cells (MNC). In this study, we compared, by oligonucleotide microarray, the differential gene expression profiles of basal and LPS-activated APB vs CB Mo. We demonstrated a significant increase in the gene expression of several important functional groups of CB genes compared with basal levels including cytokine (IL-12p40, 5-fold), immunoregulatory (signaling lymphocytic activation molecule, 4-fold), signal transduction (Pim-2, 3-fold), and cell structure (Rho7, 4-fold) among others. Furthermore, there was significantly differentially amplified gene expression in LPS-activated APB vs LPS-activated CB Mo, including cytokine (G-CSF, 14-fold), chemokine (macrophage-inflammatory protein 1alpha, 5-fold), immunoregulatory (MHC DRB1, 5-fold), transcription factor (JunB, 4-fold), signal transduction (STAT4, 5-fold), apoptotic regulation (BAX, 5-fold), and cell structure (ladinin 1, 6-fold) among others. These results provide insight into the molecular basis for normal genetic regulation of Mo development and cellular function and differential inflammatory and innate and adaptive immune responses between activated CB and APB Mo.

Adjuvants, Immunologic↗

A decision analysis of allogeneic bone marrow transplantation for the myelodysplastic syndromes: delayed transplantation for low-risk myelodysplasia is associated with improved outcome.

Bone marrow transplantation (BMT) can cure myelodysplastic syndrome (MDS), although transplantation carries significant risks of morbidity and mortality. Because the optimal timing of HLA-matched BMT for MDS is unknown, we constructed a Markov model to examine 3 transplantation strategies for newly diagnosed MDS: transplantation at diagnosis, transplantation at leukemic progression, and transplantation at an interval from diagnosis but prior to leukemic progression. Analyses using individual patient risk-assessment data from transplantation and nontransplantation registries were performed for all 4 International Prognostic Scoring System (IPSS) risk groups with adjustments for quality of life (QoL). For low and intermediate-1 IPSS groups, delayed transplantation maximized overall survival. Transplantation prior to leukemic transformation was associated with a greater number of life years than transplantation at the time of leukemic progression. In a cohort of patients under the age of 40 years, an even more marked survival advantage for delayed transplantation was noted. For intermediate-2 and high IPSS groups, transplantation at diagnosis maximized overall survival. No changes in the optimal transplantation strategies were noted when QoL adjustments were incorporated. For low- and intermediate-1-risk MDS, delayed BMT is associated with maximal life expectancy, whereas immediate transplantation for intermediate-2- and high-risk disease is associated with maximal life expectancy.

Adolescent↗

A pilot study of tacrolimus and mycophenolate mofetil graft-versus-host disease prophylaxis in childhood and adolescent allogeneic stem cell transplant recipients.

Tacrolimus (FK506)/mycophenolate mofetil (MMF) has been demonstrated to be an effective salvage therapy for steroid-resistant chronic graft-versus-host disease (GVHD), but its effectiveness as prophylaxis for acute GVHD (aGVHD) is unknown. We investigated the safety and efficacy of FK506/MMF in preventing aGVHD and sparing the use of methotrexate and methylprednisolone in childhood and adolescent allogeneic stem cell transplant (AlloSCT) recipients. Thirty-four childhood and adolescent patients (median age, 7 years; range, 0.5-21 years; 24 males and 10 females) undergoing 37 AlloSCTs for malignant (n = 22) and nonmalignant (n = 12) disorders received FK506 (0.03 mg/kg/d by continuous intravenous infusion) and MMF (15 mg/kg per dose orally or intravenously twice daily). Stem cell sources included 22 umbilical cord blood donors (21 unrelated and 1 related), 6 related bone marrow donors, and 9 related peripheral blood donors. Malignant diagnoses included 7 acute lymphoblastic leukemias, 3 acute myeloid leukemias, 1 acute promyelocytic leukemia, 2 non-Hodgkin lymphomas, 4 Hodgkin diseases, 3 chronic myeloid leukemias, and 2 neuroblastomas; nonmalignant diagnoses included 2 beta-thalassemias, 1 sickle cell disease, 4 aplastic anemias, 1 Wiskott-Aldrich syndrome, 1 Hurler syndrome, 2 hemophagocytic lymphohistiocytoses, and 1 myelodysplastic syndrome. The probability of developing grade > or =II aGVHD was 45.4% +/- 9.7% (7 related bone marrow/related peripheral blood; 5 umbilical cord blood), and for chronic GVHD it was 38.1% +/- 19.7%. FK506/MMF was well tolerated. Three patients had grade III to IV neurotoxicity (disorientation and leukoencephalopathy); 4 patients developed grade III to IV nephrotoxicity (all received concomitant nephrotoxins). Patients who achieved target mycophenolic acid levels (1.0-3.5 microg/mL) before day +30 had a significantly reduced incidence of developing grade >/=II aGVHD (16.7% +/- 15.2% versus 100%; P <.02). These results suggest that FK506/MMF is well tolerated and may be a safe and effective methotrexate- and methylprednisolone-sparing alternative GVHD prophylaxis regimen after AlloSCT. Further pharmacokinetic and pharmacodynamic studies are ongoing in pediatric and adolescent AlloSCT recipients to define optimal MMF dosing.

Adolescent↗

Chromosome abnormalities may correlate with prognosis in Burkitt/Burkitt-like lymphomas of children and adolescents: a report from Children's Cancer Group Study CCG-E08.

Among pediatric non-Hodgkin lymphomas, the most frequent type is small noncleaved-cell lymphoma (including Burkitt and Burkitt-like). Specific chromosome abnormalities are associated with prognosis in childhood acute lymphoblastic leukemia (ALL); however, chromosome abnormalities have not been evaluated for prognostic value in pediatric Burkitt and Burkitt-like lymphomas. For Children's Cancer Group protocol CCG-E-08 Etiologic Study of Non-Hodgkin Lymphoma in Childhood, 19 patients were enrolled with cytogenetic analysis of Burkitt or Burkitt-like lymphoma and simultaneously enrolled on treatment protocols CCG-503 or CCG-552. Pathology material and karyotypes at initial diagnosis underwent central review. Demographics included an age range of 2 to 14 years (median 8 years) and a male:female ratio of 14:5. All patients had advanced disease (stages III and IV, or ALL). Disease relapsed in five patients (event-free survival 74%, median follow-up 10.4 years). Chromosome abnormalities were identified in 18 patients (95%) including t(8;14)(q24.1;q32) in 12 (63%); t(8;22)(q24.1;q11.2) in 1 (5%); partial duplication of 1q in 7 (37%); and 13q32 abnormalities in 2 (11%). In patients who had relapses, in addition to the t(8;14)(q24. ;q32), two had abnormalities of 13q32 and two had partial duplication of 1q. CMYC translocations were absent in Burkitt-like lymphomas from all three patients. Burkitt and Burkitt-like lymphomas in children have a high frequency of chromosome abnormalities. Burkitt lymphoma abnormalities often involve CMYC translocations, usually a t(8;14)(q24.1;q32). Additional chromosome abnormalities that involved 13q32 and partial duplication of 1q were associated with poor prognosis. Burkitt-like lymphomas were not associated with CMYC translocations. Further studies are warranted in larger cohorts of children and adolescents with Burkitt and Burkitt-like lymphomas.

Adolescent↗

Tumour lysis syndrome: new therapeutic strategies and classification.

Tumour lysis syndrome (TLS) describes the metabolic derangements that occur with tumour breakdown following the initiation of cytotoxic therapy. TLS results from the rapid destruction of malignant cells and the abrupt release of intracellular ions, nucleic acids, proteins and their metabolites into the extracellular space. These metabolites can overwhelm the body's normal homeostatic mechanisms and cause hyperuricaemia, hyperkalaemia, hyperphosphaetemia, hypocalcaemia and uraemia. TLS can lead to acute renal failure and can be life-threatening. Early recognition of patients at risk and initiation of therapy for TLS is essential. There is a high incidence of TLS in tumours with high proliferative rates and tumour burden such as acute lymphoblastic leukaemia and Burkitt's lymphoma. The mainstays of TLS prophylaxis and treatment include aggressive hydration and diuresis, control of hyperuricaemia with allopurinol prophylaxis and rasburicase treatment, and vigilant monitoring of electrolyte abnormalities. Urine alkalinization remains controversial. Unfortunately, there have been few comprehensive reviews on this important subject. In this review, we describe the incidence, pathophysiological mechanisms of TLS and risk factors for its development. We summarise recent advances in the management of TLS and provide a new classification system and recommendations for prophylaxis and/or treatment based on this classification scheme.

Allopurinol↗