title: Solitary Langerhans-cell histiocytosis of the clivus and sphenoid sinus with parasellar and petrous extensions: case report and a review of literature.
abstract: BACKGROUND
  In Langerhans-cell histiocytosis, there occurs an uncontrolled clonal proliferation of dendritic cells that have Langerhans cell like characteristics. In this report, a unique case of a solitary, skull base Langerhans-cell histiocytosis (LCH) is described.
  
  
  METHODS
  A 15-year-old boy presented with raised intracranial pressure, decreased visual acuity, bilateral abducent nerve palsy, and 25% hypoesthesia in all three divisions of the right trigeminal nerve. He had normal strength but with a left-sided upper and lower limb hypertonia and hyper-reflexia and an upgoing plantar reflex. The magnetic resonance (MR) imaging revealed a heterogeneously iso-to hyperintense lesion of the clivus and the sphenoid sinus, extending to the right cavernous sinus to encase the right cavernous internal carotid artery segment, and also involving the right petrous apex and the extradural space in the prepontine region. The lesion was brilliantly enhancing on contrast. An extended frontobasal approach was used to excise the lesion. Following surgery, the residual parasellar and the right petrous apex tumor was treated with a low dose radiation therapy. At follow-up after 1.5 years, there was significant clinical improvement and the computed tomographic scan showed no residual lesion.
  
  
  CONCLUSIONS
  A review of the literature reveals that this is only the second reported case of a spheno-clival LCH. An additional feature includes extensions into the parasellar as well as the petrous apex regions. Despite the extensive spread, the surgical excision with low dose radiation therapy was successful in providing complete resolution of the tumor.
authors.affiliation: Department of Neurosurgery, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, India.
authors.forename: Himanshu
authors.initials: H
authors.lastname: Krishna
authors.forename: Sanjay
authors.initials: S
authors.lastname: Behari
authors.forename: Lily
authors.initials: L
authors.lastname: Pal
authors.forename: Apjit K
authors.initials: AK
authors.lastname: Chhabra
authors.forename: Deepu
authors.initials: D
authors.lastname: Banerji
authors.forename: Devendra K
authors.initials: DK
authors.lastname: Chhabra
authors.forename: Vijendra K
authors.initials: VK
authors.lastname: Jain
mesh_terms: D000293:Adolescent; D003388:Cranial Fossa, Posterior / Q000473:pathology* / Q000601:surgery*; D006646:Histiocytosis, Langerhans-Cell / Q000473:pathology* / Q000532:radiotherapy / Q000601:surgery*; D006801:Humans; D007427:Intracranial Pressure; D008279:Magnetic Resonance Imaging; D008297:Male; D013101:Sphenoid Sinus / Q000473:pathology* / Q000601:surgery*; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome