title: Synchronous tumours of the unilateral parotid gland: rare or undetected?
abstract: BACKGROUND
  Multiple tumours of the parotid gland with the same histological appearance may occur as synchronous unilateral tumours, but bilaterality has also been reported. Synchronous multiple unilateral parotid tumours with different histology remain rare.
  
  
  METHODS
  Between January 1988 and May 2002, a total of 341 patients underwent parotidectomy in our department. Medical charts were reviewed retrospectively for synchronous multiple unilateral tumours.
  
  
  RESULTS
  Fourteen patients had two or more tumours within the same specimen. The combinations encountered were two to four adenolymphomas (n=9), adenolymphoma plus pleomorphic adenoma (n=3), adenolymphoma plus MALT lymphoma (n=1), and pleomorphic adenoma plus acinic cell carcinoma (n=1). The outcome was clinical freedom from signs of tumour recurrence in any patient (mean follow-up = 51 months).
  
  
  CONCLUSIONS
  Synchronous multiple unilateral parotid tumours usually include two or more adenolymphomas and might occur more often than previously realized. The possibility of a concomitant carcinoma, and the prevention of recurrent tumours, may warrant a more radical surgical excision of the parotid gland, accurate intraoperative examination of the resected specimen, and routine histological evaluation of the entire specimen. Preoperative radiological investigation may further increase the chances of finding multiple parotid tumours.
authors.affiliation: Department of Surgery, Medisch Spectrum Twente, The Netherlands. czeebregts@hotmail.com
authors.forename: Clark J
authors.initials: CJ
authors.lastname: Zeebregts
authors.forename: Walter J B
authors.initials: WJ
authors.lastname: Mastboom
authors.forename: Gerard
authors.initials: G
authors.lastname: van Noort
authors.forename: Rob J
authors.initials: RJ
authors.lastname: van Det
mesh_terms: D000235:Adenolymphoma / Q000473:pathology / Q000601:surgery; D008949:Adenoma, Pleomorphic / Q000473:pathology / Q000601:surgery; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018267:Carcinoma, Acinar Cell / Q000473:pathology / Q000601:surgery; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007430:Intraoperative Care; D018442:Lymphoma, B-Cell, Marginal Zone / Q000473:pathology / Q000601:surgery; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000473:pathology; D009378:Neoplasms, Multiple Primary / Q000473:pathology* / Q000601:surgery; D010306:Parotid Gland / Q000601:surgery; D010307:Parotid Neoplasms / Q000473:pathology* / Q000601:surgery; D018714:Radiotherapy, Adjuvant; D012189:Retrospective Studies; D016896:Treatment Outcome