Presentation, treatment, and outcomes of unifocal and multifocal osseous vertebral Langerhans cell histiocytosis lesions in patients under 18 years old.

Abstract

This study aims to (1) clinically and radiographically characterize a series of unifocal (single-system single-site) and multifocal (single-system multiple-site) langerhans cell histiocytosis (LCH) lesions in the vertebra and (2) determine the success and recurrence rates with different treatment modalities in a pediatric population at a tertiary children's hospital. Patients younger than 18 years old with a diagnosis of LCH before 1 June 2021 at our institution were reviewed. The inclusion criteria were a unifocal or multifocal vertebral lesion without systemic disease. Clinical presentations, lesion sites, radiographic findings, treatments, complications, recurrence rates, and length of follow-up were reviewed and recorded. Thirty-nine patients had unifocal (36%) or multifocal (64%) vertebral lesions. 44% of patients had vertebral lesions only. The most common clinical presentation was neck or back pain (51%) and difficulty or inability to ambulate (15%). 70 vertebrae were involved in total; 59% cervical, 62% thoracic, 49% lumbar, and 10% sacral. 88% of multifocal patients underwent chemotherapy compared to 60% of unifocal patients. The recurrence rate in the entire cohort was 10%. The median length of follow-up was 5.2 years (0.6-16.8). Chemotherapy is often utilized as a treatment for vertebral LCH lesions regardless of unifocal or multifocal osseous presentation, with good outcomes and low recurrence rates. However other treatments such as observation only and steroid injections may be a better option with smaller and less widespread lesions due to side effects and length of treatment with chemotherapy. Determination of more invasive treatments including surgical excision or fixation will need to be considered on a case-by-case basis. Level of evidence: IV.