title: Detection of alveolar rhabdomyosarcoma in pleural fluid with immunocytochemistry on cell block and determination of PAX/FKHR fusion mRNA by reverse transcription-polymerase chain reaction.
abstract: BACKGROUND
  Alveolar rhabdomyosarcoma is a primitive malignant round cell neoplasm, which shows skeletal muscle differentiation. Although their histopathologic and immunohistochemical findings are well known, the cytology, immunocytochemistry and molecular study on pleural effusion have not been well documented.
  
  
  OBJECTIVE
  To apply molecular method in the diagnosis and monitoring of alveolar rhabdomyosarcoma.
  
  
  METHODS
  The case of a 14-year-old Thai male, who presented with dyspnea and left pleural effusion. Computed tomography of the chest and abdomen showed a huge heterogeneous enhancing mass at the left retroperitoneum. Pleural fluid cytology showed malignant small round blue cells. Immunocytochemical stains on cell block material showed positive reactivity to vimentin, sarcomeric actin, desmin, MyoD1, myogenin, and CD56 in round cell tumor Reverse transcription-polymerase chain reaction (RT-PCR) demonstrated PAX/FKHR fusion transcript. The patient received chemotherapeutic regimen for advanced-stage rhabdomyosarcoma. Finally, he succumbed to the disease, thirteen months after the diagnosis.
  
  
  CONCLUSIONS
  Immunocytochemistry on cell block in conjunction with determination of PAX/FKHR fusion mRNA by RT-PCR is a molecular method in the diagnosis and monitoring of alveolar rhabdomyosarcoma inpleural fluid.
authors.affiliation: Department of Pediatric, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand.
authors.forename: Ruchchadol
authors.initials: R
authors.lastname: Sawangpanich
authors.forename: Noppadol
authors.initials: N
authors.lastname: Larbcharoensub
authors.forename: Artit
authors.initials: A
authors.lastname: Jinawath
authors.forename: Atcharaporn
authors.initials: A
authors.lastname: Pongtippan
authors.forename: Usanarat
authors.initials: U
authors.lastname: Anurathapan
authors.forename: Suradej
authors.initials: S
authors.lastname: Hongeng
mesh_terms: D000293:Adolescent; D003584:Cytological Techniques; D017809:Fatal Outcome; D000071161:Forkhead Box Protein O1; D051858:Forkhead Transcription Factors / Q000235:genetics*; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D015514:Oncogene Proteins, Fusion / Q000235:genetics*; D051761:Paired Box Transcription Factors / Q000235:genetics*; D016066:Pleural Effusion, Malignant / Q000209:etiology; D012186:Retroperitoneal Neoplasms / Q000150:complications / Q000175:diagnosis* / Q000235:genetics* / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D018232:Rhabdomyosarcoma, Alveolar / Q000150:complications / Q000175:diagnosis* / Q000235:genetics* / Q000378:metabolism
chemical_list: C085126:FOXO1 protein, human; D000071161:Forkhead Box Protein O1; D051858:Forkhead Transcription Factors; D015514:Oncogene Proteins, Fusion; D051761:Paired Box Transcription Factors