title: Differential diagnosis of pulmonary carcinoma following head and neck cancer by genetic analysis.
abstract: OBJECTIVE
  Patients with head and neck cancer often develop a lung tumor that can be diagnosed as distant metastasis (DM) or second primary tumor (SPT). In this study, we use TP53 mutation analysis for validation of an allelic loss marker panel and a decision algorithm for distinguishing between DM and SPT.
  
  
  METHODS
  Tumor pairs of 39 patients were analyzed for TP53 mutations, for patterns of allelic loss and immunohistochemical analysis of p53 expression. Results of these three analyses were compared, using mutation analysis as gold standard.
  
  
  RESULTS
  Loss of heterozygosity (LOH) analysis indicated DM in 15 and SPT in 23 cases (one inconclusive). TP53 mutation analysis was informative in 15 cases. Based on the p53 mutation status alone, nine tumors were diagnosed as SPT and six as DM. In all 15 cases the LOH analysis was in concordance with the TP53 mutation analysis. Immunostaining for p53 showed promise as a first scan to diagnose lung tumors as SPT but cannot be used to diagnose DM.
  
  
  CONCLUSIONS
  The TP53 mutation data validate the suitability of the LOH marker panel and decision algorithm for differential diagnosis of DM and SPT in the lung. LOH analysis can theoretically be exploited in almost all cases and is less laborious than TP53 mutation analysis.
authors.affiliation: Department of ORL, Academic Medical Center, Amsterdam, Tumor Biology Section, Amsterdam, The Netherlands.
authors.forename: T W
authors.initials: TW
authors.lastname: Geurts
authors.forename: M L F
authors.initials: ML
authors.lastname: van Velthuysen
authors.forename: F
authors.initials: F
authors.lastname: Broekman
authors.forename: T Hooft
authors.initials: TH
authors.lastname: van Huysduynen
authors.forename: M W M
authors.initials: MW
authors.lastname: van den Brekel
authors.forename: N
authors.initials: N
authors.lastname: van Zandwijk
authors.forename: H
authors.initials: H
authors.lastname: van Tinteren
authors.forename: P
authors.initials: P
authors.lastname: Nederlof
authors.forename: A J M
authors.initials: AJ
authors.lastname: Balm
authors.forename: R H
authors.initials: RH
authors.lastname: Brakenhoff
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D002294:Carcinoma, Squamous Cell / Q000175:diagnosis* / Q000235:genetics / Q000556:secondary; D004252:DNA Mutational Analysis; D003937:Diagnosis, Differential; D005260:Female; D016158:Genes, p53; D006258:Head and Neck Neoplasms / Q000235:genetics* / Q000473:pathology; D006801:Humans; D019656:Loss of Heterozygosity; D008175:Lung Neoplasms / Q000175:diagnosis* / Q000235:genetics; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis / Q000175:diagnosis; D016609:Neoplasms, Second Primary / Q000175:diagnosis* / Q000235:genetics