OBJECTIVES: To study the clinical characteristics, efficacy, and prognosis of pediatric Langerhans cell histiocytosis (LCH). METHODS: A retrospective analysis was conducted on 72 children with newly diagnosed LCH. RESULTS: The median age of the 72 children was 5 years (range: 0-14 years), with skull involvement being the most common (56 cases, 77.8%). The BRAF-V600E mutation was not associated with clinical characteristics, efficacy, or prognosis (P>0.05). The 5-year overall survival rate was 91.6%±4.2%, and the 5-year event-free survival (EFS) rate was 67.5%±5.8%. The 6-week chemotherapy response rate and 5-year EFS rate were lower in the risk organ involvement group compared to the no risk organ involvement group (P<0.05). The five-year overall survival rates for the group with multi-system involvement and the group with platelet count ≥450×10⁹/L were respectively lower than those for the single-system involvement group and the group with platelet count <450×10⁹/L (P<0.05). Risk organ involvement is an independent risk factor for 5-year EFS (P<0.05). CONCLUSIONS Skull is the most commonly affected site in pediatric LCH. The BRAF-V600E mutation is not related to clinical characteristics, efficacy, or prognosis. Elevated platelet count, risk organ involvement, and multisystem involvement are associated with poor prognosis, with risk organ involvement being an independent risk factor for 5-year EFS.
Humans ; Histiocytosis, Langerhans-Cell/therapy* ; Child, Preschool ; Child ; Male ; Infant ; Female ; Adolescent ; Retrospective Studies ; Proto-Oncogene Proteins B-raf/genetics* ; Prognosis ; Infant, Newborn ; Mutation

This report describes a case of adult temporal bone Langerhans cell histiocytosis（LCH） that presented as posterior canal dehiscence syndrome（PCDS）. The patient initially presented with vertigo, tinnitus, and hearing loss. Computed tomography（CT） revealed erosive changes in the mastoid and posterior semicircular canal. After the operation, the patient's hearing and vestibular symptoms disappeared and postoperative recovery was favorable. Adult LCH is relatively rare, and this case serves as an example to discuss the clinical features and treatment options of this disease, followed by a literature review.
Humans ; Histiocytosis, Langerhans-Cell/complications* ; Semicircular Canal Dehiscence/etiology* ; Temporal Bone/pathology*

Langerhans cell histiocytosis of bone is a rare tumor disease characterized by the large accumulation of CD1a⁺ and CD207⁺ dendritic cells in tissues of unknown cause.It mainly occurs in children aged 1-4 years old,with incidences of 4-6 per million in children and 1-2 per million in adults.Due to its low incidence,diverse clinical manifestations,and no obvious specificity of imaging manifestations,the definitive diagnosis and early treatment of this type of tumor are challenging.In this paper,we report 8 cases of Langerhans cell histiocytosis of bone and review the relevant literature published in the past five years to summarize the clinical characteristics,pathological features,diagnosis,treatment,and prognosis of this disease.
Humans ; Bone Diseases/therapy* ; Histiocytosis, Langerhans-Cell/therapy*

Langerhans Cell Histiocytosis (LCH) is a rare disorder characterized by the abnormal proliferation of histiocytes, predominantly affecting the bones and skin. However, it can also involve the bone marrow, liver, spleen, lungs, pituitary gland, central nervous system, and other organs. The disorder is named for the neoplastic cells that resemble dendritic Langerhans cells found in the skin and mucosa.

We present the case of a 2-year-old Filipino female diagnosed with recurrent LCH, highlighting the diagnostic challenges and therapeutic interventions encountered. The patient initially presented with characteristic papules and plaques indicative of LCH. Initial treatment involved multi-agent chemotherapy, which resulted in significant clinical improvement. However, following the cessation of therapy, the patient experienced recurrence of symptoms, necessitating reevaluation. A skin punch biopsy confirmed the diagnosis of LCH, reinforcing the decision to reinitiate chemotherapy. Complications arose during treatment, including febrile neutropenia, which required hospitalization and adjustments to the management plan. After completing the chemotherapy cycles, the patient demonstrated marked clinical improvement, with the resolution of systemic symptoms and a reduction in the severity of cutaneous lesions.

This case underscores the complexities in managing recurrent LCH in pediatric patients. A comprehensive diagnostic evaluation, vigilant monitoring for treatment-related complications, and prompt therapeutic interventions are critical for achieving optimal outcomes. Effective management requires a multidisciplinary approach to address the unique challenges presented, ensuring timely interventions to improve patient outcomes.

Langerhans cell histiocytosis (LCH) is an inflammatory myeloid neoplasia affecting children 2-5 years old. The clinical presentation ranges from self-resolving localized disease to fulminant, fatal disseminated disease. While the most common presentation of LCH are small, translucent crusted papules on the trunk, intertriginous areas, and scalp, it may present as crusted plaques and alopecia. A 3-year-old male presented with a 4-month history of solitary, well-defined, hyperpigmented plaque with yellow-brown crust on the left parieto-occipital area of the scalp measuring 1.5 x 1.5 cm and a solitary, well-defined, hairless patch with areas of erythema on the left parieto-occipital area measuring 5.0 x 6.0 cm. Scalp biopsy revealed diffuse collection of lymphohistiocytes interspersed with distinct kidney bean-shaped cells. CD1a is positive for cells of interest. Skeletal survey revealed lytic lesions involving the skull, thoracic cage, spine, pelvis, and upper and lower extremities. The rest of the physical examination findings revealed lymphadenopathy, crackles, globular abdomen with right and left upper quadrant dullness. The patient had episodes of fever, difficulty of breathing, and abdominal pain. The patient received chemotherapy as multisystem LCH based on prednisone and vinblastine. Following 3 courses of chemotherapy, there is noted hair regrowth and sloughing off of crust.

Langerhans cell histiocytosis (LCH) is a group of unexplainable abnormal proliferation and aggregation of Langerhans cell. LCH can be classified into four clinical variants: Letterer-Siwe disease, Hand-Schüller-Christian disease, eosinophilic granuloma, and congenital self-healing LCH. LCH is most prevalent in children. Lesions can be localized in a single system or multiple organs, and clinical manifestations vary depending on the affected organs. The skin and mucocutaneous tissues are the starting point of the affected tissue. This study presents a LCH case characterized by transient self-healing. This case can further provide references for the clinical diagnosis and treatment of LCH.
Child ; Humans ; Histiocytosis, Langerhans-Cell/therapy* ; Diagnosis, Differential

Thyroid involvement in Langerhans Cell Histiocytosis (LCH) is rare. We report a 10-year-old Filipino male who presented with a rapidly enlarging goiter. Computed tomography scan showed thyroid and bilateral submandibular masses with malignant features, pulmonary blebs and hepatic cysts. Ultrasound-guided core needle biopsy findings were consistent with LCH and chemotherapy was initiated. This case demonstrates that LCH should be considered in patients with goiter. Multidisciplinary management is warranted to achieve proper diagnosis and institute timely treatment.
Histiocytosis, Langerhans-Cell ; Thyroid Gland

Objective: To analyze the efficacy, safety, and long-term prognosis of intermediate-dose cytarabine (Ara-c) regimen in the treatment of children with refractory risk organ involvement Langerhans cell histiocytosis (LCH). Methods: Clinical data of 17 children with multisystem and risk organ involvement LCH who failed the first-line therapy and were treated with intermediate-dose Ara-c (250 mg/m², twice daily) regimen in the Hematology Center, Beijing Children's Hospital from January 2013 to December 2016 were analyzed retrospectively. In addition to the basic treatment of vindesine and dexamethasone, the patients received two regimens: regimen A: the intermediate-dose Ara-c combined with cladribine and regimen B: the intermediate-dose Ara-c alone. The efficacy, safety and prognosis of the two regimens were analyzed. Results: Among all 17 patients, there were 11 males and 6 females, with the diagnosis age of 2.1 (1.6, 2.7) years. Ten children received regimen A, all of them achieved active disease-better (AD-B) after 8 courses of induction therapy. The disease activity scores (DAS) decreased from 5.5 (3.0, 9.0) to 1.0 (0, 2.3). Seven children received regimen B, and 6 of them achieved AD-B after 8 courses of induction therapy. The DAS decreased from 4.0 (2.0, 4.0) to 1.0 (0, 2.0). The follow-up time was 6.2 (4.9,7.2) and 5.2 (3.7,5.8) years in group A and B. The 5-year overall survival rate was 100.0% in both groups, and the 5-year event free survival rate was (88.9±10.5)% and (85.7±13.2)% in group A and B. Grade 3 or 4 myelosuppression was observed in 8 patients in group A and 2 patients in group B. Conclusions: The intermediate-dose Ara-c regimen (with or without cladribine) is effective and safe for patients with refractory high-risk LCH, with a good long-term prognosis.
Male ; Female ; Child ; Humans ; Cytarabine/adverse effects* ; Cladribine/adverse effects* ; Retrospective Studies ; Antineoplastic Combined Chemotherapy Protocols/adverse effects* ; Histiocytosis, Langerhans-Cell/drug therapy* ; Prognosis

Adult ; Humans ; Stomach ; Histiocytosis, Langerhans-Cell/diagnosis*

Humans ; Anaplastic Lymphoma Kinase ; Histiocytosis, Langerhans-Cell ; Receptor Protein-Tyrosine Kinases ; Lymphoma, Large-Cell, Anaplastic/pathology*