Corinne Armari-Alla

BRAF Mutation Correlates With High-Risk Langerhans Cell Histiocytosis and Increased Resistance to First-Line Therapy

PURPOSE Langerhans cell histiocytosis (LCH) is an inflammatory myeloid neoplasia with a broad spectrum of clinical manifestations and outcomes in children. The somatic BRAF(V600E) mutation occurs frequently, but clinical significance remains to be determined. PATIENTS AND METHODS BRAF(V600E) mutation was investigated in a French LCH cohort. We analyzed associations between mutation status and clinical presentation, extent of disease, reactivation rate, response to therapy, and long-term permanent sequelae. RESULTS Among 315 patients with successfully determined BRAF status, 173 (54.6%) carried a BRAF(V600E) mutation. Patients with BRAF(V600E) manifested more severe disease than did those with wild-type BRAF. Patients with BRAF(V600E) comprised 87.8% of patients (43 of 49) with multisystem LCH with risk organ involvement (liver, spleen, hematology), 68.6% of patients (35 of 51) with multisystem LCH without risk organ involvement, 43.9% of patients (86 of 196) with single-system LCH, and 42.1% of patients (8 of 19) with lung-involved LCH (P < .001). BRAF(V600E) mutation was also associated with organ involvement that could lead to permanent, irreversible damage, such as neurologic (75%) and pituitary (72.9%) injuries. Compared with patients with wild-type BRAF, patients with BRAF(V600E) more commonly displayed resistance to combined vinblastine and corticosteroid therapy (21.9% v 3.3%; P = .001), showed a higher reactivation rate (5-year reactivation rate, 42.8% v 28.1%; P = .006), and had more permanent, long-term consequences from disease or treatment (27.9% v 12.6%; P = .001). CONCLUSION In children with LCH, BRAF(V600E) mutation was associated with high-risk features, permanent injury, and poor short-term response to chemotherapy. Further population-based studies should be undertaken to confirm our observations and to assess the impact of BRAF inhibitors for this subgroup of patients who may benefit from targeted therapy.

Rituximab therapy for childhood Evans syndrome

The safety and efficacy of rituximab have been retrospectively assessed in 17 children with Evans syndrome. Patients received 4 or 3 weekly doses of rituximab (375 mg/m2 per dose) associated with prednisone, alone (14 patients) or associated with other immunosuppressive drugs. Complete or partial remission of at least one cytopenia was achieved in 13 out of the 17 patients (76%), and lasted in 11 of them with a mean follow-up of 2.4 years (range 0.5–7 years). Steroid therapy was stopped or tapered at 50–100% of the baseline dosage in all long-term responders. Moderate side effects and infection occurred only in 4 and 1 children respectively.

Langerhans cell histiocytosis: therapeutic strategy and outcome in a 30‐year nationwide cohort of 1478 patients under 18 years of age

The French national cohort of children with Langerhans cell histiocytosis (LCH) has included 1478 patients since it was established in 1983. LCH therapeutic strategies substantially changed in 1998, so we have divided the cohort into two 15‐year periods. Starting in 1998, therapy duration increased from 6 to 12 months, repeated induction therapy was performed in cases showing a poor response to the first induction with vinblastine and steroids, and refractory disease in a risk organ (RO+) was treated with cladribine and cytarabine. A total of 483 (33%) patients were enrolled before 1998, and 995 (67%) after 1998. Five‐year survival was 96·6% (95% confidence interval: 95·4–97·5%) overall, improving from 92% pre‐1998 to 99% post‐1998 (P < 0·001 adjusted to disease extent). This change was supported by an increase in 5‐year survival from 60% to 92% in the RO+ group. Survival was particularly associated with cladribine and cytarabine among refractory RO+ patients. Disease reactivation was slightly less frequent after 1998, due to better enrolment of single‐system patients, extended therapy duration, and more efficient second‐line therapy. The crude rates of endocrine and neurological sequelae (the most frequent sequelae) appeared to improve over time, but this difference was not observed when the analysis was stratified by disease extent.

Thymus and mediastinal node involvement in childhood langerhans cell histiocytosis: Long-term follow-up from the French national cohort

Mediastinal involvement (MI) in Langerhans cell histiocytosis (LCH) has been rarely reported. Here, we describe the clinical, radiological, and biological presentation, and the outcome of childhood LCH with MI.

Familial history of cancer and childhood acute leukemia: a French population-based case-control study.

A case–control study was conducted to investigate the role of a familial history of cancer in the etiology of childhood acute leukemia. The history of cancer in the relatives of 472 cases was compared with that of 567 population-based controls. Recruitment was frequency matched on age, sex and region. The familial history of cancer in each childs relatives was reported by the mother in response to a standardized self-administered questionnaire. A familial history of solid tumor in first or second-degree relatives was associated with an increased risk of acute lymphoblastic leukemia (odds ratio (OR)=1.6 [95% confidence interval, 1.2–2.1]), while a familial history of hematopoietic malignancies in first or second-degree relatives was associated with an increased risk of acute myeloid leukemia (OR=4.3 [1.4–13]). The ORs for the histories of cancer increased with the number of relatives with cancer (OR=1.5 [1.1–2.0] for one relative and OR=2.3 [1.3–3.8] for two relatives or more; Ptrend<0.0001). Significant associations between childhood acute leukemia and familial history of genital cancers and brain tumor were also observed (OR=2.7 [1.2–5.8] and OR=10.7 [1.3–86], respectively). This study supports the hypothesis that a familial history of cancer may play a role in the etiology of childhood acute leukemia. It also evidences some specific associations that require further investigation.

Evans Syndrome in Children: Long-Term Outcome in a Prospective French National Observational Cohort

Evans syndrome (ES) is a rare autoimmune disorder whose long-term outcome is not well known. In France, a collaborative pediatric network set up via the National Rare Disease Plan now provides comprehensive clinical data in children with this disease. Patients aged less than 18 years at the initial presentation of autoimmune cytopenia have been prospectively included into a national observational cohort since 2004. The definition of ES was restricted to the simultaneous or sequential association of autoimmune hemolytic anemia (AIHA) and immune thrombocytopenic purpura (ITP). Cases were deemed secondary if associated with a primitive immunodeficiency or systemic lupus erythematosus. In December 2014, we analyzed the data pertaining to 156 children from 26 centers with ES whose diagnosis was made between 1981 and 2014. Median age (range) at the onset of cytopenia was 5.4 years (0.2–17.2). In 85 sequential cases, the time lapse between the first episodes of AIHA and ITP was 2.4 years (0.1–16.3). The follow-up period as from ES diagnosis was 6.5 years (0.1–28.8). ES was secondary, revealing another underlying disease, in 10% of cases; various associated immune manifestations (mainly lymphoproliferation, other autoimmune diseases, and hypogammaglobulinemia) were observed in 60% of cases; and ES remained primary in 30% of cases. Five-year ITP and AIHA relapse-free survival were 25 and 61%, respectively. Overall, 69% of children required one or more second-line immune treatments, and 15 patients (10%) died at the age of 14.3 years (1.7–28.1). To our knowledge, this is the first consistent long-term clinical description of this rare syndrome. It underscores the high rate of associated immune manifestations and the burden of long-term complications and treatment toxicity. Future challenges include (1) the identification of the underlying genetic defects inducing immune dysregulation and (2) the need to better characterize patient subgroups and second-line treatment strategies.

Academic Difficulties and Occupational Outcomes of Adult Survivors of Childhood Leukemia Who Have Undergone Allogeneic Hematopoietic Stem Cell Transplantation and Fractionated Total Body Irradiation Conditioning

We studied academic and employment outcomes in 59 subjects who underwent allogeneic hematopoietic stem cell transplantation (a-HSCT) with fractionated total body irradiation (fTBI) for childhood leukemia, comparing them with, first, the general French population and, second, findings in 19 who underwent a-HSCT with chemotherapy conditioning. We observed an average academic delay of 0.98 years among the 59 subjects by Year 10 of secondary school (French class Troisième), which was higher than the 0.34-year delay in the normal population (P < .001) but not significantly higher than the delay of 0.68 years in our cohort of 19 subjects who underwent a-HSCT with chemotherapy. The delay was dependent on age at leukemia diagnosis, but not at fTBI. This delay increased to 1.32 years by the final year of secondary school (Year 13, Terminale) for our 59 subjects versus 0.51 years in the normal population (P = .0002), but did not differ significantly from the 1.08-year delay observed in our cohort of 19 subjects. The number of students who received their secondary school diploma (Baccalaureate) was similar to the expected rate in the general French population for girls (observed/expected = 1.02) but significantly decreased for boys (O/E = 0.48; CI: 95%[0.3–0.7]). Compared with 13.8% of the general population, 15.3% of the cancer survivors received no diploma (P = NS). Reported job distribution did not differ significantly between our cohort of childhood cancer survivors and the general population except that more female survivors were employed in intermediate-level professional positions. Academic difficulties after fTBI are common and their early identification will facilitate educational and professional achievement.

Childhood immune thrombocytopenia: A nationwide cohort study on condition management and outcomes

Nationwide prospective cohort study exploring (i) the factors associated with treatment initiation (vs. watchful waiting) in children with primary immune thrombocytopenia (ITP) followed in routine clinical practice and (ii) the predictors of chronicity at 12 months.

Benefits of rituximab as a second-line treatment for autoimmune haemolytic anaemia in children: a prospective French cohort study

Childhood autoimmune haemolytic anaemia (AIHA) requires second‐line immunosuppressive therapy in 30–50% of cases. It appears that rituximab is indicated in such circumstances. This prospective national study reports the practice, efficacy and tolerance of rituximab in children with isolated AIHA and AIHA in the setting of Evans syndrome (ES). Sixty‐one children were given rituximab between 2000 and 2014. The median interval from diagnosis to rituximab was 9·9 [interquartile range (IQR) 1·6–28·5] months. Forty‐six patients responded (75%) and the 6‐year relapse‐free survival (RFS) was 48%. Twenty patients relapsed at a median interval of 10·8 (IQR 3·9–18·7) months, rituximab allowed steroid withdrawal in 44/61 (72%) of children. In isolated AIHA, complete response and 6‐year RFS were significantly higher than in ES (P < 0·05). Ten out of 61 patients were infants, seven of who responded with a 6‐year RFS of 71%. Among patients without immunoglobulin substitution before rituximab, 4 are still receiving substitutions. Five patients died, including one potentially attributable to rituximab. This large observational series of childhood AIHA established the rituximab benefit‐risk ratio, allowing steroid withdrawal, with 37% of long‐term responders, mainly in isolated AIHA. All subgroups of patients drew benefit. Our long‐term results indicate the baseline to be challenged by new treatment approaches.

Final height and body mass index after fractionated total body irradiation and allogeneic stem cell transplantation in childhood leukemia.

Impaired linear growth has been reported in patients treated during childhood with allogeneic stem cell transplantation and fractionated total body irradiation (fTBI). The objective of this study was to determine the final height and body mass index (BMI) achieved. Forty-nine patients with leukemia were included and surveyed for more than 5 years. Median age at follow-up was 24.3 years (range, 18.9–35.8) and median follow-up time from allograft was 14.4 years (range, 4.5–21.9). Mean height standard deviation score (s.d.s.) at final examination (−1.1 ± 1.3,) was significantly lower than at fTBI (0.3 ± 1.2; P = .001). Final height s.d.s. was significantly correlated with age at diagnosis, age at fTBI, and target height (P = .001; P < .001; P < .001, respectively). Final height was significantly lower in children transplanted before age 5 (P = .006). Growth hormone treatment (n = 6) had only a modest effect on growth velocity. Mean BMI at follow-up was normal at 19.6 kg/m2 for boys and 21.2 for girls, but with a significant decrease since allograft only for boys (−1.2 ± 1.5 s.d.s.) (P = .003). In conclusion, final height is decreased; BMI is normal but decreased from fTBI in boys.