title: Effusion cytology of granulocytic sarcoma in an unusual clinical scenario: a diagnostic challenge.
abstract: BACKGROUND
  Presentation of granulocytic sarcoma (GS) as an effusion is very rare and most cases are misdiagnosed as lymphoma infiltration. Detailed descriptions of cytological features of GS in an effusion have not been published to date.
  
  
  METHODS
  We present the case of a 35-year-old male who presented clinically with a mediastinal mass, peripheral lymphadenopathy and pleural/pericardial effusion. His effusion cytology showed an atypical morphology. Immature cells with marked nuclear indentation/convolution, fine nuclear chromatin, conspicuous nucleoli and a moderate amount of cytoplasm were seen, without any granularity. GS was suspected based on the abnormal nuclear contours and fine nuclear chromatin, and was confirmed by lymph node fine needle aspiration and biopsy with immunocytochemistry.
  
  
  CONCLUSIONS
  Abnormal nuclear contours are a significant marker in effusion cytology and provide an important morphological clue to the diagnosis of a myeloid malignancy in addition to fine nuclear chromatin especially in the absence of cytoplasmic granularity. In this case, these features helped to suspect the diagnosis despite a clinical scenario suggestive of non-Hodgkin's lymphoma.
authors.affiliation: Department of Pathology, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Geetika
authors.initials: G
authors.lastname: Singh
authors.forename: Shipra
authors.initials: S
authors.lastname: Agarwal
authors.forename: Venkateswaran K
authors.initials: VK
authors.lastname: Iyer
authors.forename: Atul
authors.initials: A
authors.lastname: Sharma
authors.forename: Anita
authors.initials: A
authors.lastname: Chopra
authors.forename: Sandeep R
authors.initials: SR
authors.lastname: Mathur
mesh_terms: D000328:Adult; D003581:Cytodiagnosis / Q000379:methods; D003937:Diagnosis, Differential; D006801:Humans; D008228:Lymphoma, Non-Hodgkin / Q000175:diagnosis / Q000473:pathology; D008297:Male; D008479:Mediastinal Neoplasms / Q000175:diagnosis / Q000473:pathology*; D010490:Pericardial Effusion / Q000209:etiology / Q000473:pathology*; D010996:Pleural Effusion / Q000209:etiology / Q000473:pathology*; D023981:Sarcoma, Myeloid / Q000175:diagnosis / Q000473:pathology*