Presentations, treatment and outcomes of unifocal and multifocal osseous appendicular Langerhans cell histiocytosis lesions in a pediatric population

• Published in: World journal of pediatric surgery Vol. 6; no. 1; p. e000483
• Main Authors: Ezeokoli, Ekene U, Mitchell, Parker, Schlehr, Eva, Borici, Neritan, Montgomery, Nicole
• Format: Journal Article
• Language: English
• Published: England BMJ Publishing Group Ltd 01.02.2023; BMJ Publishing Group LTD; BMJ Publishing Group
• Subjects: Autoimmune diseases; Biopsy; Bone Diseases; Bones; Chemotherapy; Fractures; Letter; Magnetic resonance imaging; Musculoskeletal Diseases; Orthopedics; Patients; Pediatrics; Population; Radiation therapy; Rib cage; Steroids; Vertebrae; Bone Diseases; Musculoskeletal Diseases; Orthopedics
• DOI: 10.1136/wjps-2022-000483
• ISSN: 2516-5410; 2096-6938

Correspondence to Dr Ekene U Ezeokoli; ekenex@gmail.com Langerhans cell histiocytosis (LCH) is a rare disease most commonly presenting in the pediatric population and characterized by neoplastic clonal proliferation of Langerhans dendritic cells with accumulation in various sites, including skeletal and visceral lesions.1 There are three levels of classification per the Histiocyte Society: single-system single-site (SS-s), single-system multiple-site (SS-m), and multisystem (MS).2 SS-s predominantly carries a better prognosis with more conservative treatment while MS requires a more aggressive treatment that is more likely to have an inferior outcome. Clinical presentations, lesion sites, additional skeletal lesions, biopsy site, focal classification, radiographic findings, lesion size, treatments, complications, recurrence rates, and length of follow-up, if present, were reviewed and recorded. The median age at diagnosis was 6.5 years (range: 0.7–16.7 years) (table 1).Table 1 Demographics and characteristics Variable Counts (percentages) Sex  Male 14 (47%)  Female 16 (53%) Age at diagnosis (years)* 6.5 (0.7–16.7) Location  Femur only 14 (47%)  Humerus only 8 (27%)  Tibia only 5 (17%)  Tibia+femur 2 (7%)  Fibula 1 (3%) Additional skeletal lesions  Skull/maxillofacial 5 (17%)  Pelvis 4 (13%)  Vertebrae 4 (13%)  Ribs/sternum 2 (7%)  Clavicle 1 (3%) Classification  Unifocal 18 (60%)  Multifocal 12 (40%) Radiographs  Fractures 4 (13%)  Lytic lesions 22 (73%) Immunopathology  CD1a+ 23 (77%)  CD68+ 7 (23%)  CD207+ 19 (63%)  S100+ 12 (40%) *Data are presented with median (range). AP, anteriorposterior; MRI, magnetic resonance imaging Table 2 Treatment and outcomes Variable Counts (percentage) Treatment  Curettage only 5 (17%)  Curettage total 8 (27%)  Steroid injection only 6 (20%)  Chemotherapy only 13 (43%)  Biopsy only 4 (13%)  Radiotherapy 1 (3%) Chemotherapy involved in treatment  Vinblastine+prednisone 11 (37%)  Cytarabine 3 (10%)  6-mercaptopurine 3 (10%)  Methotrexate 2 (7%)  Clofarabine 1 (3%)  Cladribine 1 (3%) Recurrence rate (any site)  All 8 (27%)  Curettage or steroid only 4 (37%) Total follow-up (years)* 5.2 (0.6–16.8) *Data are presented with median (range).