title: Polymorphous low-grade adenocarcinoma: a case series and determination of recurrence.
abstract: OBJECTIVE
  Information on polymorphous low-grade adenocarcinoma (PLGA) consists primarily of case reports and small institutional series with varying recurrence rates. In this report, we describe our institutional experience and conduct a review of the literature to assess the overall incidence of PLGA among oral salivary gland tumors and determine recurrence rates.
  
  
  METHODS
  A retrospective case series and literature-based review was performed.
  
  
  METHODS
  Retrospective case series at an academic tertiary referral center. Review of clinical records and pathological analysis of tissue specimens from 20 patients treated for PLGA from July 1, 1990 to July 1, 2011. A literature-based review on PLGA was also performed.
  
  
  RESULTS
  Twenty patients (mean age, 54 years; eight males) with PLGA based on pathologic diagnosis were included. The most common initial presentation was an asymptomatic mass (45%), and the most frequent site was the palate (60%). Our literature review identified 54 case reports, eight case series, and 17 large series. In total, 456 cases of PLGA were identified, with an overall recurrence rate of 19%. Half of the recurrences occurred by 36 months; however, recurrences were reported up to 24 years after initial resection.
  
  
  CONCLUSIONS
  PLGA arises from minor salivary glands and is characteristically slow growing and indolent. Although these tumors may be histologically low-grade, our review highlights the high rates of recurrence of these tumors as well as the ability to metastasize to local lymph nodes and distant organs. The mainstay of treatment should be wide surgical excision with long-term oncologic follow-up.
  
  
  METHODS
  4.
authors.affiliation: Department of Otolaryngology/Head and Neck Surgery, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, U.S.A.
authors.forename: Adam J
authors.initials: AJ
authors.lastname: Kimple
authors.forename: Grace K
authors.initials: GK
authors.lastname: Austin
authors.forename: Rupali N
authors.initials: RN
authors.lastname: Shah
authors.forename: Chris M
authors.initials: CM
authors.lastname: Welch
authors.forename: William K
authors.initials: WK
authors.lastname: Funkhouser
authors.forename: Adam M
authors.initials: AM
authors.lastname: Zanation
authors.forename: William W
authors.initials: WW
authors.lastname: Shockley
mesh_terms: D000230:Adenocarcinoma / Q000175:diagnosis / Q000601:surgery*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003937:Diagnosis, Differential; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis* / Q000453:epidemiology; D009367:Neoplasm Staging; D009657:North Carolina / Q000453:epidemiology; D012189:Retrospective Studies; D012307:Risk Factors; D012468:Salivary Gland Neoplasms / Q000175:diagnosis / Q000601:surgery*; D012470:Salivary Glands, Minor
keywords: Polymorphous low-grade adenocarcinoma (PGLA); minor salivary gland tumor