title: Fine needle aspiration cytology of primary lymphoid lesions of the orbit: report of four cases.
abstract: BACKGROUND
  The role offine needle aspiration cytology (FNAC) in diagnosis and differentiation of primary orbital lymphoid lesions is debatable, and little literature exists on cytodiagnosis of orbital lymphoid lesions.
  
  
  METHODS
  Four patients with orbital lesions underwent routine FNAC. In 3 cases, histopathologic examination was performed with immunohistochemistry (IHC). Cytologic features and diag- noses were correlated with histopathologic diagnoses. Two were cytologically diagnosed with low-grade non-Hodgkin lymphoma (NHL) and 2 with pseudolymphoma and inflammatory pseudotumor, respectively. Of the 2 cases of histologically diagnosed NHL, 1 had concordant diagnosis and the other had a jalse negative diagnosis of pseudolymphoma; both showed significant increase in mast cells, with neoplastie lymphoid cells exhibiting a higher N:C ratio and coarser chromatin texture. The case cytologically interpreted as suspicious for NHL was identified as a psetedolymphoma on histology (false positive). The case of inflammatory pseudotumor, in which hiopiy was not peiformned, responded well to corticosteroids, strengthening the cytologic diagnosis.
  
  
  CONCLUSIONS
  FNAC diagnosis and differentiation of benign vs. malignant primacy orbital lymphoid lesions is often difficult. Careful cytologic interpretation with respect to certain subtle cytologic details is needed in minimizing false positive or false negative diagnoses. In difficult situations, IHC using suitable immunomarkers proves highly useful.
authors.affiliation: Department of Pathology, Jawaharlal Institute of Postgraduate Medical Education and Research, Pondicherry, India.
authors.forename: Rajiv
authors.initials: R
authors.lastname: Subramanian
authors.forename: Seyiechutuo
authors.initials: S
authors.lastname: Solo
authors.forename: Manisha Manaswini
authors.initials: MM
authors.lastname: Mishra
authors.forename: Paari
authors.initials: P
authors.lastname: Murugan
authors.forename: Neelaiah
authors.initials: N
authors.lastname: Siddaraju
authors.forename: Debdatta
authors.initials: D
authors.lastname: Basu
authors.forename: Renuka
authors.initials: R
authors.lastname: Srinivasan
mesh_terms: D000328:Adult; D000368:Aged; D044963:Biopsy, Fine-Needle; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008228:Lymphoma, Non-Hodgkin / Q000175:diagnosis / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009915:Orbit / Q000473:pathology*; D016727:Orbital Pseudotumor / Q000175:diagnosis / Q000473:pathology*; D019310:Pseudolymphoma / Q000175:diagnosis / Q000473:pathology*