title: Carcinoma ex pleomorphic adenoma: diagnostic difficulty and outcome.
abstract: OBJECTIVE
  To analyze a series of carcinoma ex pleomorphic adenoma (CXPA) and to assess the diagnostic difficulties.
  
  
  METHODS
  The clinical presentation of 24 CXPAs was compared with 300 pleomorphic adenomas (PAs). Furthermore, pathohistological findings and follow-up results of CXPAs were evaluated.
  
  
  RESULTS
  Eight of 24 (33%) CXPAs versus 41 of 300 (14%) PAs were localized in the deep lobe (P < 0.05). Forty-two percent of CXPAs versus 6 percent of PAs, respectively, were greater than 4 cm (P < 0.05). The sensitivity in detecting CXPA by fine-needle aspiration cytology (FNAC) was 47 percent. The tumor was known to be malignant preoperatively in 10 (42%) patients. Six of 24 (25%) patients with CXPA developed a tumor recurrence. The overall 5-year survival rate of CXPA was 76 percent.
  
  
  CONCLUSIONS
  CXPAs are difficult to identify preoperatively. FNAC has a low accuracy and sensitivity. CXPAs versus PAs are significantly more frequently localized in the deep lobe and are significantly greater in size.
authors.affiliation: Department of Otorhinolaryngology, Head, and Neck Surgery, University Hospital, Berne, Switzerland. peter.zbaeren@insel.ch
authors.forename: Peter
authors.initials: P
authors.lastname: Zbären
authors.forename: Sibylle
authors.initials: S
authors.lastname: Zbären
authors.forename: Marco D
authors.initials: MD
authors.lastname: Caversaccio
authors.forename: Edouard
authors.initials: E
authors.lastname: Stauffer
mesh_terms: D008949:Adenoma, Pleomorphic / Q000473:pathology*; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002277:Carcinoma / Q000473:pathology*; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010307:Parotid Neoplasms / Q000473:pathology*