Efficacy of single-agent cytarabine in adult langerhans cell histiocytosis: Short report and summary of treatment data for a rare disease

Abstract

Langerhans Cell Histiocytosis (LCH) in adults is rare and has little prospective data to guide therapy. We describe a 36 year old gentleman who presented with a three-month history of isolated cervical lymphadenopathy, from which excision biopsy revealed sheets of large, atypical cells 10-15 um in size, with indented nuclei and fine chromatin along with eosinophilic microabscesses. Immunohistochemistry was positive for CD3, CD20, CD68, CD1a, S100, CD4, Langerin (CD207) and CD45 with a Ki67 index of 10%. PET scan showed FDG-avid uptake in left mastoid air cells, which was confirmed by MRI to indicate bony involvement with disease. Bone marrow and CSF were normal. He was diagnosed as multisystem LCH without risk organ involvement and initiated on single agent cytarabine at 100 mg/m2 five days a month. A PET scan after three cycles showed near complete metabolic resolution. He has completed six cycles of the same and is asymptomatic. He is planned for continuation of Cytarabine for another of 12 to 14 months. Single agent cytarabine appears safe and effective for adult patients with LCH. We provide a short summary of available data: compilation of prospective data will further clarify the utility of this regimen in adult patients with LCH.

Keywords

• blood
• cancer
• langerhans cell histiocytosis
• lymphoma