title: Positron emission tomography and stage migration in head and neck cancer.
abstract: OBJECTIVE
  Since 2001, there has been a rapid adoption of positron emission tomography (PET) for diagnosis and American Joint Committee on Cancer (AJCC) staging of head and neck cancer (HNC) without data describing improved clinical outcomes.
  
  
  OBJECTIVE
  To determine the association between increased use of PET and stage and/or survival for patients with HNC in the managed care environment.
  
  
  METHODS
  Adult patients diagnosed as having HNC (n = 958) from 2000 to 2008 at 4 integrated health systems were identified via tumor registries linked to administrative data. The AJCC stage distribution, patient and treatment characteristics, and survival between pre-PET era (2000-2004) vs PET era (2005-2008) and use of PET vs no use of PET during the PET era were compared. The AJCC stages were categorized to represent localized (stage I or II), locally advanced (stage III, IVA, or IVB), and metastatic (stage IVC) disease.
  
  
  METHODS
  Treatments were determined by billing codes for surgery, radiation treatment, and chemotherapy.
  
  
  METHODS
  The primary outcome for this study was the use of PET. Secondary outcomes included treatment received and 2-year survival. A logit model estimated the effects of PET on diagnosis of locally advanced disease. Kaplan-Meier estimates described overall survival differences between PET and non-PET. Cox regression evaluated the association of PET on survival in patients with locally advanced disease.
  
  
  RESULTS
  An association between PET and locally advanced disease was found (odds ratio, 2.86 [95% CI, 1.90-4.29) (P < .001). Two-year overall survival for patients with locally advanced disease with and without PET was 52% and 32%, respectively (P = .004), but there was no difference for all stages (P = .69). On Cox proportional hazard regression, PET had no association with survival in patients with locally advanced disease (hazard ratio, 1.208 [95% CI, 0.778-1.877]) (P = .40).
  
  
  CONCLUSIONS
  The increasing use of PET among patients with HNC is associated with a greater number of patients with higher-stage disease and a dilution of the population with higher-stage disease with patients who have a better prognosis. Thus, the improved survival in patients with locally advanced disease likely reflects selection bias and stage migration. Further research on PET use among patients with HNC is necessary to determine if it results in improved treatment for individual patients.
authors.affiliation: Department of Radiation Oncology, University of North Carolina at Chapel Hill2Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill.
authors.forename: Noam A
authors.initials: NA
authors.lastname: VanderWalde
authors.affiliation: Department of Health Services Policy and Management, Arnold School of Public Health, University of South Carolina, Columbia.
authors.forename: Ramzi G
authors.initials: RG
authors.lastname: Salloum
authors.affiliation: Department of Health Policy and Management, Gillings School of Public Health, University of North Carolina at Chapel Hill.
authors.forename: Tsai-Ling
authors.initials: TL
authors.lastname: Liu
authors.affiliation: The Center for Health Research, Kaiser Permanente Northwest, Portland, Oregon.
authors.forename: Mark C
authors.initials: MC
authors.lastname: Hornbrook
authors.affiliation: The Center for Health Research, Kaiser Permanente Northwest, Portland, Oregon.
authors.forename: Maureen C
authors.initials: MC
authors.lastname: O'Keeffe Rosetti
authors.affiliation: Institute for Health Research, Kaiser Permanente Colorado, Denver.
authors.forename: Debra P
authors.initials: DP
authors.lastname: Ritzwoller
authors.affiliation: Group Health Research Institute, Group Health Cooperative, Seattle, Washington.
authors.forename: Paul A
authors.initials: PA
authors.lastname: Fishman
authors.affiliation: Social and Behavioral Health and Massey Cancer Center, School of Medicine Virginia Commonwealth University, Richmond9Center for Health Policy and Health Services Research, Henry Ford Health System, Detroit, Michigan.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Elston Lafata
authors.affiliation: Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill10Division of Nuclear Medicine, Department of Radiology, University of North Carolina at Chapel Hill.
authors.forename: Amir H
authors.initials: AH
authors.lastname: Khandani
authors.affiliation: Department of Radiation Oncology, University of North Carolina at Chapel Hill2Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill.
authors.forename: Bhishamjit S
authors.initials: BS
authors.lastname: Chera
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D019788:Fluorodeoxyglucose F18; D006258:Head and Neck Neoplasms / Q000401:mortality / Q000473:pathology* / Q000628:therapy; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging / Q000379:methods*; D049268:Positron-Emission Tomography; D016016:Proportional Hazards Models
chemical_list: D019788:Fluorodeoxyglucose F18