Germline TET2 loss of function causes childhood immunodeficiency and lymphoma.

Molecular dissection of inborn errors of immunity can help to elucidate the nonredundant functions of individual genes. We studied 3 children with an immune dysregulation syndrome of susceptibility to infection, lymphadenopathy, hepatosplenomegaly, developmental delay, autoimmunity, and lymphoma of B-cell (n = 2) or T-cell (n = 1) origin. All 3 showed early autologous T-cell reconstitution following allogeneic hematopoietic stem cell transplantation. By whole-exome sequencing, we identified rare homozygous germline missense or nonsense variants in a known epigenetic regulator of gene expression: ten-eleven translocation methylcytosine dioxygenase 2 (TET2). Mutated TET2 protein was absent or enzymatically defective for 5-hydroxymethylating activity, resulting in whole-blood DNA hypermethylation. Circulating T cells showed an abnormal immunophenotype including expanded double-negative, but depleted follicular helper, T-cell compartments and impaired Fas-dependent apoptosis in 2 of 3 patients. Moreover, TET2-deficient B cells showed defective class-switch recombination. The hematopoietic potential of patient-derived induced pluripotent stem cells was skewed toward the myeloid lineage. These are the first reported cases of autosomal-recessive germline TET2 deficiency in humans, causing clinically significant immunodeficiency and an autoimmune lymphoproliferative syndrome with marked predisposition to lymphoma. This disease phenotype demonstrates the broad role of TET2 within the human immune system.

The use of anthracyclines in the treatment of endemic Burkitt lymphoma.

Burkitt lymphoma is the most common malignancy in children in Malawi, the world's poorest country, where there is a long history of treating this disease using a 28-day cyclophosphamide-based protocol. Stage III/IV disease has had poor outcomes. In an attempt to improve the outcome for higher stage disease, anthracyclines were added to the existing protocol. The disease-free (DFS) and overall survival (OS) of 58 children with cytologically confirmed Burkitt lymphoma admitted during 2012-2014 and treated using this protocol were calculated. Six (10%) children had stage I disease, ten (17%) stage II and 42 stage III or IV (73%). Overall 12-month DFS (OS) was 68·5% (72·9%); for stage I disease 100% (100%), stage II 56·2% (60%), stage III/IV 66·3% (72·2%). The DFS was significantly improved from the previous protocol (P = 8 × 10-4 ). The addition of doxorubicin to stage III and IV disease resulted in a markedly improved DFS. Anthracyclines are deliverable in resource-poor settings and possibly improve the survival of children with Burkitt lymphoma.

Lack of bone lesions at diagnosis is associated with inferior outcome in multisystem langerhans cell histiocytosis of childhood.

Skeletal involvement is generally, but not universally, characteristic of Langerhans cell histiocytosis (LCH). We investigated whether the presence of bone lesions at diagnosis is a prognostic factor for survival in LCH. Nine hundred and thirty-eight children with multisystem (MS) LCH, both high (386 RO+) and low (RO-) risk, were evaluated for bone lesions at diagnosis. Risk organ (RO+) involvement was defined as: haematopoietic system (haemoglobin <100 g/l, and/or white blood cell count <4·0 × 10(9) /l and/or platelet count <100 × 10(9) /l), spleen (>2 cm below the costal margin), liver (>3 cm and/or hypoproteinaemia, hypoalbuminaemia, hyperbilirubinaemia, and/or increased aspartate transaminase/alanine transaminase). Given the general view that prognosis in LCH worsens with increasing extent of disease, the surprising finding was that in MS+RO+ LCH the probability of survival with bone involvement 74 ± 3% (n = 230, 56 events) was reduced to 62 ± 4% (n = 156, 55 events) if this was absent (P = 0·007). An even greater difference was seen in the subgroup of patients with both liver and either haematopoiesis or spleen involvement: 61 ± 5% survival (n = 105; 52 events) if patients had bony lesions, versus 47 ± 5% (n = 111; 39 events) if they did not (P = 0·014). This difference was retained in multivariate analysis (P = 0·048). Although as yet unexplained, we conclude that bone involvement at diagnosis is a previously unrecognized favourable prognostic factor in MS+RO+ LCH.

Therapy prolongation improves outcome in multisystem Langerhans cell histiocytosis.

Langerhans cell histiocytosis (LCH)-III tested risk-adjusted, intensified, longer treatment of multisystem LCH (MS-LCH), for which optimal therapy has been elusive. Stratified by risk organ involvement (high [RO+] or low [RO-] risk groups), > 400 patients were randomized. RO+ patients received 1 to 2 six-week courses of vinblastine+prednisone (Arm A) or vinblastine + prednisone + methotrexate (Arm B). Response triggered milder continuation therapy with the same combinations, plus 6-mercaptopurine, for 12 months total treatment. 6/12-week response rates (mean, 71%) and 5-year survival (84%) and reactivation rates (27%) were similar in both arms. Notably, historical comparisons revealed survival superior to that of identically stratified RO+ patients treated for 6 months in predecessor trials LCH-I (62%) or LCH-II (69%, P < .001), and lower 5-year reactivation rates than in LCH-I (55%) or LCH-II (44%, P < .001). RO- patients received vinblastine+prednisone throughout. Response by 6 weeks triggered randomization to 6 or 12 months total treatment. Significantly lower 5-year reactivation rates characterized the 12-month Arm D (37%) compared with 6-month Arm C (54%, P = .03) or to 6-month schedules in LCH-I (52%) and LCH-II (48%, P < .001). Thus, prolonging treatment decreased RO- patient reactivations in LCH-III, and although methotrexate added no benefit, RO+ patient survival and reactivation rates have substantially improved in the 3 sequential trials. (Trial No. NCT00276757 www.ClinicalTrials.gov).

Langerhans cell histiocytosis in children with congenital anomalies: a population-based record linkage study.

BACKGROUND: The etiology of Langerhans cell histiocytosis (LCH), a rare cancer-like disorder of the immune system, is largely unknown although a genetic component has been suggested based on familial cases, and reports of chromosome instability and genetic mutation. Associations between various cancers and congenital anomalies have been reported and although congenital anomalies have been noted in children with LCH only one study to date has reported their frequency. An association between congenital anomalies and LCH may suggest a common etiological pathway, in particular, a genetic pathway. METHODS: Data from two coterminous registries in the same geographic region were used. All cases of LCH on the Northern Region Young Persons Malignant Disease Register diagnosed between 1985 and 2010 were cross-matched with live-born cases of congenital anomaly registered by the Northern Congenital Abnormality Survey. RESULTS: A total of 819,890 children and young people were born during 1985 to 2008. Of these, 13,799 (1.7%) had a congenital anomaly and 39 (0.005%) were diagnosed with LCH. Three LCH cases were identified among those with congenital anomalies, all three of whom had congenital heart disease. The relative risk of LCH for those with a congenital anomaly, compared with those without, was 4.87 (95% confidence interval, 1.50-15.81; p = 0.03). CONCLUSION: LCH was associated with congenital anomaly in a small but statistically significant number of patients, raising the possibility of a common genetic pathway in some cases.

Cutaneous B-lymphoblastic lymphoma with IL3/IgH translocation presenting with hypereosinophilia and acute endocarditis.

Hypereosinophilia is a rare phenomenon associated with childhood malignancy, predominantly acute lymphoblastic leukaemia. Causation is unclear and likely to have multiple mechanisms. We report a six year old boy presenting with hypereosinophilia and associated Loeffler endocarditis. Three months following his initial hypereosinophilia he developed cutaneous B-lymphoblastic lymphoma. Re-analysis of apparently uninvolved bone marrow, taken at initial presentation, revealed a single, previously unidentified, t(5;14)(q31;q32) positive cell. Using fluorescent in situ hybridisation, we demonstrate IL3/IgH@ fusion in cutaneous lymphoma cells. Our case confirms the association of hypereosinophilia and B-lymphoblastic lymphoma and strengthens the association between IL3 hypersecretion and hypereosinophilia.

Transplantation for congenital heart disease is associated with an increased risk of Epstein-Barr virus-related post-transplant lymphoproliferative disorder in children.

BACKGROUND: Children undergoing heart transplant are at higher risk of developing post-transplant lymphoproliferative disorder (PTLD) than other solid organ recipients. The factors driving that risk are unclear. This study investigated risk factors for PTLD in children transplanted at 1 of 2 United Kingdom pediatric cardiac transplantation centers. METHODS: All children (<18 years, n = 200) transplanted at our institution over a 16-year period were analyzed. Freedom from PTLD was assessed using the Kaplan-Meier method and Cox proportional regression. RESULTS: PTLD occurred in 17 of 71 children transplanted for congenital heart disease (CHD) and 18 of 129 transplanted for acquired cardiomyopathy (ACM). The cumulative incidence of all PTLD was 21.1% at 5 years after transplant. Median time from transplant to PTLD was 2.9 years (interquartile range: 0.9-4.6). Negative Epstein-Barr virus (EBV) serostatus pre-transplant (adjusted hazard ratio [HR]: 2.7, 95% CI: 1.3-5.6, p = 0.01) and underlying CHD (adjusted HR: 3.2, 95% CI: 1.4-7.4, p = 0.007) were independently associated with higher risk of PTLD. Age at thymectomy was significantly different between children with CHD and ACM (0.4 vs 5.5 years, p < 0.01). Median CD4+ and CD8+ T lymphocyte counts at 2 years after transplant were significantly lower in children transplanted for CHD vs ACM (CD4+: 391/µl vs 644/µl, p = 0.01; CD8+: 382/µl vs 500/µl, p = 0.01). At 5 years after transplant, those differences persisted among patients who developed PTLD (CD4+, 430/µl vs 963/µl, p < 0.01 and CD8+, 367/µl vs 765/µl, p < 0.01). CONCLUSION: Underlying CHD is an independent risk factor for PTLD and is associated with a younger age at thymectomy. A persistent association with altered T lymphocyte subsets may contribute to the impaired response to primary EBV infection and increase the risk of PTLD.

Post cardiac transplantation lymphoproliferative disorder presenting as t(8;14) Burkitt leukaemia/lymphoma treated with low intensity chemotherapy and rituximab.

BACKGROUND: Post-transplant lymphoproliferative disorder (PTLD) occasionally presents as Burkitt lymphoma/L3 leukaemia (BLL). PROCEDURE: We reviewed records of cases of PTLD post-cardiac transplantation (1990-2007) occurring in our unit. RESULTS: There were 15 episodes in 13 patients including four cases of EBV-driven Burkitt-type disease with t(8;14) translocations presenting with advanced stage disease. The first case was treated with a variety of low dose chemotherapy combinations. Despite problems during therapy he obtained complete remission, but died from complications of pre-existing cardiac allograft vasculopathy 7 months later. The subsequent three cases were treated with a UKCCSG low stage lymphoma protocol, NHL 9001 and Rituximab. They remain in complete remission. CONCLUSIONS: In the context of PTLD the prognostic significance of advanced stage EBV-driven BLL with the t(8;14) translocation may be different to that in immunocompetent children.

Reactivations in multisystem Langerhans cell histiocytosis: data of the international LCH registry.

OBJECTIVE: To assess multisystem Langerhans cell histiocytosis reactivation and its impact on morbidity and mortality. STUDY DESIGN: Retrospective analysis of 335 patients with MS-LCH and documented complete disease resolution (NAD1). RESULTS: The probability of a reactivation within 5 years of NAD1 was 46%. The first reactivation occurred within 2 years after NAD1 in most of the patients. Of 134 events, 35% were confined to skeleton, 24% were single-system nonbony lesions, 24% were multisystem reactivations without risk-organ involvement, and 10% with risk-organ involvement. In 7%, the location was unspecified. Only 3 deaths (2.2%) were documented within the context of a first reactivation. Second disease resolution (NAD2) was achieved in 85% of the cases. The probability of a second reactivation within 5 years of NAD2 was 44%. The risk for permanent consequences in patients with reactivations was higher, compared with patients without reactivation (RHR 2.2, P = .046). CONCLUSIONS: Reactivation is a frequent and early event in MS-LCH, but involvement of risk organs at reactivation is rare and mortality is minimal. However, reactivations increase the risk for permanent consequences by about 2-fold. Prospective trials targeting reduction of acute morbidity and permanent disabilities through nontoxic treatment of the reactivations are warranted.

Do as I say or die: compliance in adolescents with cancer.

Adolescence is a time of great physical change and maturing brain function. This leads to adolescents establishing independence and coming to terms with the implications of their own actions. Not surprisingly, this phase is characterized by experimentation with both constructive and destructive behavior. Studies in many areas of chronic illness have shown that adolescents frequently neglect their care and revolt against the rules established during their childhood. It is therefore to be expected that teenagers diagnosed with a life threatening illness, such as cancer, may on occasion not fully comply with their therapy. The way forward includes improving communication and fully involving these young persons in their treatment planning, thereby moving from compliance to concordance. Additional improvements should be sought in medication, early recognition and support of familial or social problems, and using a specific adolescent multidisciplinary team. Research should not be limited to clinical trials.

Epidemiology of leukaemia and lymphoma in children and young adults from the north of England, 1990-2002.

AIM: We aimed to describe and contrast the epidemiology of haematological malignancies among 0-14 and 15-24-year-olds in northern England from 1990 to 2002 and compare clinical trial entry by age group. PATIENTS AND METHODS: Incidence rates were examined by age, sex and period of diagnosis and differences were tested using Poisson regression. Differences and trends in survival were assessed using Cox regression. RESULTS: 1680 subjects were included comprising 948 leukaemias and 732 lymphomas. Incidence rates for acute lymphoblastic leukaemia were significantly higher for 0-14 compared to 15-24-year-olds, whilst Hodgkin lymphoma showed the reverse. No significant changes in incidence were observed. 60% of leukaemia patients aged 15-24 years entered trials compared to 92% of 0-14-year-olds. Survival rates were significantly lower and improved less markedly over time for 15-24 compared to 0-14-year-olds, particularly for leukaemia. CONCLUSIONS: Trial accrual rates need to be improved amongst 15-24-year-olds and a more structured follow-up approach adopted for this unique population.

Juvenile xanthogranuloma associated with contralateral lymphadenopathy.

Juvenile xanthogranuloma is an uncommon, benign histiocytic condition, primarily affecting children less than 1 year of age. Although usually only cutaneous lesions are found, systemic manifestations of the disease have been reported. We present a child with juvenile xanthogranuloma of the right cheek associated with contralateral cervical lymph node histiocytic infiltration.

Cancer in adolescents and young adults aged 15-24 years: a report from the North of England young person's malignant disease registry, UK.

BACKGROUND: Descriptions of population-based data have rarely been published specifically for adolescents and young adults with cancer. PROCEDURE: Data on young adults (15-24 years) diagnosed with cancer in the North of England from 1968 to 1997 were obtained from the Northern Region Young Person's Malignant Disease Registry. Temporal changes in incidence and survival rates were investigated. RESULTS: There were 2,329 first cancers diagnosed over the study period (M:F 1.22:1). Overall age standardized incidence was 174 cases per million 15-24 years old, per year, 190 for males and 157 for females. The most common cancers in young adults were Hodgkin disease (19%), carcinomas (15%), central nervous system tumors (14%), germ cell tumors (13%), and leukemia (11%). Comparing incidence for 1968-1977 with 1988-1997 there were significant increases in the incidence of bone tumors (rate ratio 1.72, 95% CI 1.10-2.68), testicular tumors (rate ratio 1.64, 95% CI 1.16-2.32), thyroid cancer (rate ratio 2.63, 95% CI 1.37-5.02), and malignant melanoma (rate ratio 2.04, 95% CI 1.36-3.08). Survival rates improved significantly (P < 0.001) over the study period; 5-year survival rates over the three time periods 1968-1977, 1978-1987, 1988-1997 for all cancers were 45% (95% CI 41%-49%), 62% (95% CI 58%-65%), and 74% (95% CI 71%-77%) respectively. CONCLUSIONS: Survival rates improved and there were significant increases in incidence for specific cancers in young adults in the North of England. Further research is required to identify the reasons for changing incidence and to investigate the late effects of treatment among survivors.

Starting an adolescent cancer unit: why does it take so long?

A pragmatic approach is discussed based on the authors' differing experiences while designing new units specifically for adolescents with cancer in Leeds and Newcastle upon Tyne. Planning and implementation are complex and very time consuming. Areas to be considered include: formally identifying needs and adapting to existing local circumstances, convening a working group and involving potential stakeholders at an early stage, designing a suitable physical space, recruiting and integrating staff to create a supportive environment, obtaining financial support, and developing operational policies. For successful running of an adolescent unit, old prejudices must be disavowed and new models of medical care considered.

Factors influencing early failure of central venous catheters in children with cancer.

BACKGROUND: The authors report the results of a prospective, multicenter, multidisciplinary study of central venous catheters (CVCs) in pediatric oncology patients analyzing factors involved in early failure. METHODS: Information was collected from parent-held records on the fate of 824 devices inserted over a 20-month period, 415 of which were no longer in situ. RESULTS: Within the first 7 weeks after insertion, there were 66 failures, all occurring in external lines. Accidental dislodgement was the principal reason for CVC failure (44 of 66, 67%). Detailed analysis of the reason for failure of this large subgroup showed 11 factors individually associated with early dislodgement, of which, 4 were independently associated with failure by multivariate analysis. These 4 variables were the use of multilumen catheters, the absence of a skin exit site suture, platelet transfusion at the time of insertion, and patient age less than 2 years. CONCLUSIONS: This study confirms the multiple influences on successful CVC usage. Our analysis supports the principle of only using multilumen lines when clinically essential. The findings also support the inception of randomized studies of fixation, particularly in infants.