Pediatric pulmonary multisystem langerhans cell histiocytosis: does lung lesion severity affect the outcome?

BACKGROUND: The pediatric pulmonary multisystem Langerhans cell histiocytosis (PPM LCH) is associated with either low risk or high risk organ(s). The nodulo-cystic lung lesions although pathognomonic, yet are very variable in severity and remain a source of controversy in certifying pulmonary LCH diagnosis. The study aimed to examine the prognostic value of clinical respiratory manifestations and radiological lung lesions severity. This is through associating a CT chest triad of bilateral, extensive and diffuse lesions. It is a retrospective study of 350 LCH patients who received systemic treatment at Children's Cancer Hospital Egypt during the period from 2007 to 2020. RESULTS: Sixty-seven patients (67/350-19.1%) had PPM LCH at presentation. Severe lung lesions were present in 24 of them. The median follow-up period was 61 months (IQR: 3.4-8.3). The 5-year overall survival (OS) and event free survival (EFS) was 89% and 56.6% respectively. The EFS, for severe radiological lesions triad was 38% ± 20.7 versus 66% ± 16.2 for non-severe lesions triad p 0.002, while for presence of chest X-ray changes 27% ± 22.344 versus absence of chest X ray changes 66% ± 14.7 p 0.001, for clinical respiratory manifestations 13% ± 13.9 versus none 62% ± 22.9 p < 0.001, for RO- with severe lung lesions 47% ± 30.4 versus RO- without severe lung lesions 69% ± 5.9 p 0.04. There was a tendency for the independent prognostic impact of severe lung involvement; aHR = 1.7 (95% CI 0.92-3.13, p = 0.09). CONCLUSION: Although the lung is a low -risk organ per se in LCH, our study demonstrates a non negligeable prognostic impact of severe lung involvement in the risk stratification of pediatric LCH. This warrants further study and external validation.

Reduced-intensity therapy for pediatric lymphoblastic leukemia: impact of residual disease early in remission induction.

Legacy data show that ∼40% of children with acute lymphoblastic leukemia (ALL) were cured with limited antimetabolite-based chemotherapy regimens. However, identifying patients with very-low-risk (VLR) ALL remains imprecise. Patients selected based on a combination of presenting features and a minimal residual disease (MRD) level <0.01% on day 19 of induction therapy had excellent outcomes with low-intensity treatment. We investigated the impact of MRD levels between 0.001% and <0.01% early in remission induction on the outcome of VLR ALL treated with a low-intensity regimen. Between October of 2011 and September of 2015, 200 consecutive patients with B-precursor ALL with favorable clinicopathologic features and MRD levels <0.01%, as assessed by flow cytometry in the bone marrow on day 19 and at the end of induction therapy, received reduced-intensity therapy. The 5-year event-free survival was 89.5% (± 2.2% standard error [SE]), and the overall survival was 95.5% (± 1.5% SE). The 5-year cumulative incidence of relapse (CIR) was 7% (95% confidence interval, 4-11%). MRD levels were between 0.001% and <0.01% on day 19 in 29 patients. These patients had a 5-year CIR that was significantly higher than that of patients with undetectable residual leukemia (17.2% ± 7.2% vs 5.3% ± 1.7%, respectively; P = .02). Our study shows that children with VLR ALL can be treated successfully with decreased-intensity therapy, and it suggests that the classification criteria for VLR can be further refined by using a more sensitive MRD assay.

Skeletal involvement in children with Langerhans cell histiocytosis: healing, complications, and functional outcome.

INTRODUCTION: Skeletal involvement in children with Langerhans cell histiocytosis (LCH) is a common feature of the disease. Several options for the treatment of these skeletal lesions have been reported. We describe our experience in the treatment of skeletal involvement of LCH in this retrospective case series study, entailing anatomic distribution, pattern of healing, skeletal deformities, and functional outcome of skeletal LCH. METHODS: A retrospective analysis was conducted for patients diagnosed with LCH and having skeletal lesions in the period between 2007 and 2015. Out of a total of 229 cases, 191 (83.4%) had skeletal involvement. Bone healing was divided into partial and complete based on the size of lesion and cortical changes in plain radiograph. Skeletal deformities were serially measured. Time to pain control, resumption of weight bearing, and the final functional status of the patient were reviewed. RESULTS: The mean age at presentation was 4.4 years (3 m-14.8 y) and the mean follow-up period was 53.3 months (0.2-120.7). After screening of skeletal and extra-skeletal lesions, 59 patients (31%) had M-S (Multisystem) LCH and 132 (69%) had S-S (Single system) LCH. Unifocal bone lesions were found in 81 (42.5%) patients, and multifocal bone lesions in 110 patients (57.5%). Single or multiple bone lesions were found in the craniofacial bones in 152 patients (79.5%), femur in 19 patients, (10%), ribs in 18 patients (9.4%), spine in 15 patients (8.1%), pelvis in 14 patients (7.3%), scapula in 8 patients (4.1%), humerus in 6 (3.1%), clavicle in 6 patients (3.1%), tibia in 3 patients (1.5%), radius in 3 patients (1.5%), and the ulna in 2 patients (1%) patients. No lesions were found in the fibula, hand, or foot. Out of all skeletal lesions, 179 (93.7%) patients were treated either medically or conservatively and 12 patients (6.2%) were treated surgically. The mean time to complete healing was 5.2 months (2-12). Skeletal complications included: pathologic fractures (9 vertebra plana, 5 long bone, 1 iliac bone), deformities (9 thoracolumbar kyphosis, 2 cervical spine subluxations, 2 coxa vara deformity of the proximal femur and one flattening of iliac bone). CONCLUSION: Non-operative treatment can lead to adequate bone healing in few months period. Partial or complete remodeling of bone deformities can be observed without surgical correction. However, surgical intervention might be indicated when cervical spine affection may lead to instability and subsequent neurological affection. Functional impairment is rarely caused by skeletal lesions in LCH.

Osteonecrosis in children with acute lymphoblastic leukemia: A report from Children's Cancer Hospital Egypt (CCHE).

BACKGROUND: As survival rates for children with acute lymphoblastic leukemia (ALL) improve, awareness of treatment complications becomes important. Osteonecrosis (ON) is a serious disabling complication in treated ALL patients. The aim of the study was to define the frequency of ON identified by magnetic resonance imaging (MRI) and to study the risk factors for ON. PATIENTS AND METHODS: The frequency of ON was evaluated retrospectively in 858 patients with ALL who were diagnosed at Children's Cancer Hospital of Egypt from January 2009 to December 2012. Patients were treated with St Jude Total Therapy Study XV. RESULTS: Of 858 patients evaluated, 665 were eligible for the study and 65 (9.7%) developed ON. The cumulative 5-year incidence of ON was 11.96% (SE, 0.131%). Of 154 patients aged 10 years and older, 40 (26%) developed ON. The mean age of patients with ON was 10.7 years. The prognostic factors with a significant relationship with ON were age 10 years and older (P = 0.0001) and intermediate-/high-risk group (P = 0.0001). However, gender did not have a significant relationship. At the onset of ON, the mean cumulative dexamethasone dose was 796 mg/m2 , and the mean total corticosteroid dose, calculated as prednisolone equivalence, was 6,431 mg/m2 . Out of 43 patients who developed ON while on corticosteroid therapy, 36 (84%) required dexamethasone dose modification and/or discontinuation. CONCLUSION: The frequency of ON among the studied patients was 9.7%. Risk factors with a significant association with ON were older age and more intensive corticosteroid therapy.

A Pharmacogenetic Study of VDR fok1 and TYMS Polymorphisms and Their Association With Glucocorticoid-Induced Osteonecrosis in Egyptian Children With Acute Lymphoblastic Leukemia.

Purpose: Osteonecrosis is a significant toxicity resulting from the treatment of pediatric Acute Lymphoblastic Leukemia (ALL). This study aimed to investigate the relationship between vitamin D receptor fok1 (VDR fok1) and thymidylate synthase (TYMS) gene polymorphisms with the glucocorticoid (GC) induced osteonecrosis (ON) in Egyptian pediatric ALL patients. In addition, to identify the possible association of genetic polymorphisms with other factors such as gender and ALL subtypes. Patients and Methods: A retrospective case-control study was conducted on 102 pediatric ALL patients under the age of 18 who were treated at Children Cancer Hospital Egypt according to St Jude SR/HR total XV protocol. The recruited patients were composed of 51 cases who developed GC-induced osteonecrosis and 51 age- and gender-matched patients who received glucocorticoids but remained osteonecrosis-free (controls). Genotyping of the VDR fok1 and TYMS genes was performed using restriction fragment length polymorphism (RFLP) and conventional PCR, respectively. Results: For the total 102 studied patients, the VDR fok1 single nucleotide polymorphisms (SNPs) frequency distribution were TT (8.8%), CT (34.3%), and CC (56.9%), while the TYMS tandem repeat gene variations were reported as 2R2R (20.6%), 2R3R (45.1%), and 3R3R (34.3%). VDR fok1 and TYMS polymorphic variants showed no association neither with gender; P-values 0.3808 and 0.1503, respectively, nor with ALL subtypes; P-values 0.9396 and 0.6596, respectively. The VDR fok1 polymorphisms showed a significant association with the development of ON; P-value = 0.003, on the other hand, TYMS tandem repeats did not show significant impact on osteonecrosis development; P-value = 0.411. Conclusion: This study showed a significant association between the VDR fok1 polymorphism and osteonecrosis. Such clinical pharmacogenetics results would be promising to discuss the possibility of dose adjustments aiming a regimen with the highest efficacy and least toxicity.