title: Papillary endothelial hyperplasia of the orbit: report of a case highlighting a pitfall on fine needle aspiration biopsy.
abstract: BACKGROUND
  Papillary endothelial hyperplasia (PEH) is an unusual form of thrombus organization that occurs predominantly in the extremities, including the head and neck. However, it is rare in the orbit/ocular region. Although the histologic features of PEH have been well described, the cytologic diagnosis remains difficult.
  
  
  METHODS
  A 63-year-old man presented with a left intraorbital mass that was increasing in size and associated with paresthesia and a recent history of excision of squamous cell carcinomas (SCC) from his left cheek. Fine needle aspiration biopsy (FNAB) yielded very limited material, predominantly blood. However, 1 Papanicolaou-stained slide showed groups of atypical cells with scanty but dense cytoplasm and large, hyperchromatic nuclei with prominent nucleoli. SCC was favored, and excision was performed. Histology showed PEH within an assumed cystic lymphangioma, associated with inflammatory and fibrotic change in the compressed supraorbital nerve.
  
  
  CONCLUSIONS
  To our knowledge this is the third report on the cytology of PEH and the first report of FNAB in PEH of the orbit. The case was also unusual as it was the second metachronous PEH in the patient.
authors.affiliation: Department of Anatomical Pathology, Royal Prince Alfred Hospital, Central Sydney Area Health Service, Camperdown, NSW, Australia. rooshdiya@yahoo.com.au
authors.forename: Rooshdiya Z
authors.initials: RZ
authors.lastname: Karim
authors.forename: Rohan
authors.initials: R
authors.lastname: Merani
authors.forename: Kerwin
authors.initials: K
authors.lastname: Shannon
authors.forename: Geoffrey
authors.initials: G
authors.lastname: Watson
mesh_terms: D014408:Biomarkers, Tumor / Q000032:analysis / Q000378:metabolism; D044963:Biopsy, Fine-Needle; D002294:Carcinoma, Squamous Cell / Q000175:diagnosis*; D003937:Diagnosis, Differential; D042783:Endothelial Cells / Q000473:pathology*; D006801:Humans; D006965:Hyperplasia / Q000000981:diagnostic imaging / Q000473:pathology* / Q000503:physiopathology; D018191:Lymphangioma, Cystic / Q000000981:diagnostic imaging / Q000473:pathology* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D009882:Ophthalmic Nerve / Q000473:pathology / Q000503:physiopathology / Q000601:surgery; D013508:Ophthalmologic Surgical Procedures / Q000379:methods; D009918:Orbital Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology* / Q000503:physiopathology; D011237:Predictive Value of Tests; D013927:Thrombosis / Q000209:etiology / Q000473:pathology* / Q000503:physiopathology; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
chemical_list: D014408:Biomarkers, Tumor