title: Discordance in routine second opinion pathology review of head and neck oncology specimens: A single-center five year retrospective review.
abstract: OBJECTIVE
  Second opinion review of pathology specimens is a common institutional practice, supported by large retrospective studies demonstrating significant histologic discordance. Since the most recent study of head and neck-specific pathology review was conducted, routine HPV and EBV testing is now recommended for certain specimens. We describe the frequency of and reasons for discordant reports and their potential impact on treatment recommendations and prognosis in a five-year retrospective cohort study at a single academic referral institution from 2005 to 2010.
  
  
  METHODS
  Following institutional review board review, 1003 cases referred to the Head and Neck Oncology Service were identified using a retrospective database search. Discordance between outside and second review pathology report was assessed by a board-certified medical oncologist.
  
  
  RESULTS
  667 cases were included, of which 22% were discordant. Discordance was associated with adenocarcinomas (AOR [adjusted odds ratio] 0.09, 95% CI 0.03-0.31; p<0.001), poorly differentiated carcinomas (AOR 0.14, 95% CI 0.06-0.39; p<0.001), and specimens of uncommon histology (AOR 0.18, 95% CI 0.07-0.45; p<0.001) but not biopsy site in a multivariate model. The most common reasons for discordance included histology (61%), followed by the results of special studies (36%), and the presence or absence of stromal invasion (14%). Differences in tumor HPV status comprised 16% of discordant cases and were associated with better prognosis (p<0.001) following second opinion review.
  
  
  CONCLUSIONS
  Routine second opinion pathology review may lead to clinically significant differences in treatment recommendations and prognosis.
authors.affiliation: Head and Neck Oncology Program, Stanford University School of Medicine, Stanford, CA 94305, United States.
authors.forename: Gefei Alex
authors.initials: GA
authors.lastname: Zhu
authors.affiliation: Head and Neck Oncology Program, Stanford University School of Medicine, Stanford, CA 94305, United States.
authors.forename: Ruth
authors.initials: R
authors.lastname: Lira
authors.affiliation: Head and Neck Oncology Program, Stanford University School of Medicine, Stanford, CA 94305, United States. Electronic address: colevas@stanford.edu.
authors.forename: Alexander Dimitrios
authors.initials: AD
authors.lastname: Colevas
mesh_terms: D005260:Female; D006258:Head and Neck Neoplasms / Q000473:pathology*; D006801:Humans; D008297:Male; D011379:Prognosis; D012017:Referral and Consultation / Q000592:standards*; D012189:Retrospective Studies
keywords: Biostatistics; Head and neck cancer; Historical cohort study; Multivariate analysis; Oral cancer; Pathology