title: Primitive neuroectodermal tumor of the kidney. A report of two cases diagnosed by fine needle aspiration cytology.
abstract: BACKGROUND
  Primitive neurocetodermal tumors (PNETs) constitute a family of neoplasms of presumed neuroectrodermal origin most often presenting as bone or soft tissue masses. There are very few reported cases of PNET of the kidney and none diagnosed by fine needle aspiration cytology (FNAC), to the best of our knowledge, in the world literature. We present two cases of renal PNET diagnosed on cytology.
  
  
  METHODS
  Two patients with renal masses were diagnosed as having PNET on FNAC. Cytologically the tumors showed a dispersed population of malignant small round cells with focal rosette formation and perivascular arrangement of tumor cells. Immunohistochemistry on the cell blocks in both cases showed strong membrane positivity for CD99 (MIC2). Cytogenetic studies in both cases showed the characteristic t(11;22)(q24;q12) translocation, with additional chromosomal abnormalities in case 2.
  
  
  CONCLUSIONS
  PNET of the kidney is a distinct entity and can be diagnosed on fine needle aspiration smears and confirmed with immunohistochemistry and cytogenetic studies. A diagnosis of PNET must be included in the differential diagnosis of renal masses in adolescents and young adults.
authors.affiliation: Cytopathology Unit, Department of Pathology, Kidwai Memorial Institute of Oncology, M. H. Marigowda Road, Bangalore, India 560029. prema_venka@hotmail.com
authors.forename: Chennagiri S
authors.initials: CS
authors.lastname: Premalata
authors.forename: Muniyappa
authors.initials: M
authors.lastname: Gayathri Devi
authors.forename: Siddarth
authors.initials: S
authors.lastname: Biswas
authors.forename: Geethashree
authors.initials: G
authors.lastname: Mukherjee
authors.forename: Sadashivan
authors.initials: S
authors.lastname: Balu
authors.forename: Tambarahalli S
authors.initials: TS
authors.lastname: Sundareshan
authors.forename: Ponnuswamy S
authors.initials: PS
authors.lastname: Prabhakaran
mesh_terms: D000071443:12E7 Antigen; D000328:Adult; D015703:Antigens, CD / Q000032:analysis; D000970:Antineoplastic Agents / Q000627:therapeutic use; D001707:Biopsy, Needle / Q000379:methods*; D015815:Cell Adhesion Molecules / Q000032:analysis; D002880:Chromosomes, Human, Pair 11; D002892:Chromosomes, Human, Pair 22; D020732:Cytogenetic Analysis; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007680:Kidney Neoplasms / Q000737:chemistry / Q000235:genetics / Q000473:pathology* / Q000628:therapy; D008297:Male; D009392:Nephrectomy; D018241:Neuroectodermal Tumors, Primitive, Peripheral / Q000737:chemistry / Q000235:genetics / Q000473:pathology* / Q000628:therapy; D014178:Translocation, Genetic
chemical_list: D000071443:12E7 Antigen; D015703:Antigens, CD; D000970:Antineoplastic Agents; C061828:CD99 protein, human; D015815:Cell Adhesion Molecules