Unusual Acute Onset of Symptomatic Langerhans Cell Histiocytosis of the Skull: Case Report and Literature Review

Introduction: Langerhans cell histiocytosis (LCH) is a group of idiopathic disorders characterized by the proliferation of specialized bone marrow-derived Langerhans cells (LCs) and mature eosinophils, resulting in solitary or few, indolent and chronic, lesions of bone or other organs called eosinophilic granulomas. Calvarial LCH is quite rare and an underappreciated differential etiology of skull lesions. We present a most unusual case of a young child with hyperacutely symptomatic langerhans histiocytosis of the skull. Method: A 7-year-old male presented with a history of increasing (progressive) frontal headaches of 8 days duration, unaccompanied by associated nausea, vomiting, or diplopia. His only additional complaint was a hard bump on his forehead. MRI and CT done in the ER identified a right fronto-parietal lesion with associated skull erosion. Nuclear medicine and SPECT studies confirmed an erosive skull lesion without significant metabolic activity. A right frontal craniectomy and excision was performed. Results: A soft, rubbery well-circumcised mass coming from the diploic layer of the skull with involvement of bone was identified. The mass had eroded both the outer and inner table of the skull, and the involved area of the right frontal bone was resected. Intra-operative histo-pathologic analysis of the lesion revealed Langerhans cell histiocytosis without involvement of the dura. The patient experienced no neurological worsening as a result of the resection. He was discharged home in stable condition. Conclusion: LCH lesions of the skull are common findings, however, this focal hyperacute symptomatic presentation is most rare and should not deter us from anticipating an erosive bony tumor and planning timely surgical management.