title: Earlier and more specific detection of persistent neck disease with diffusion-weighted MRI versus subsequent PET/CT after definitive chemoradiation for oropharyngeal squamous cell carcinoma.
abstract: The purpose of this study was to test if diffusion-weighted imaging (DWI) identified persistent neck disease after chemoradiotherapy (CRT) for oropharyngeal cancer earlier and as accurately as subsequent positron emission tomography (PET)/CT.
  
  
  
  We performed a review of patients with oropharyngeal cancer treated with definitive CRT who underwent DWI and PET/CT at a median of 8 and 14 weeks posttreatment. Imaging characteristics were correlated with pathologically proven neck failure.
  
  
  
  Forty-one patients and 58 hemi-necks were analyzed. With a median follow-up of 120 weeks, 4 neck failures were identified. The apparent diffusion coefficient (ADC) of lymph node failures was lower (1220 vs 1910 μm2/s; p = .003) than non-failures. Using an ADC threshold of 1500 μm2/s, the sensitivity, specificity, and positive and negative predictive values (PPV; NPV) were 100% (4/4), 92% (46/50), 50% (4/8), and 100% (46/46) for DWI, respectively, and 100% (3/3), 71% (22/31), 25% (3/12), and 100% (22/22) for PET/CT, respectively.
  
  
  
  Earlier DWI produced similar sensitivity and better specificity in identifying persistent neck disease as 3-month PET/CT. © 2016 Wiley Periodicals, Inc. Head Neck 39: 432-438, 2017.
authors.affiliation: Department of Radiation Oncology, University of California - San Francisco, San Francisco, California.
authors.forename: Yao
authors.initials: Y
authors.lastname: Yu
authors.affiliation: Department of Radiology, University of California - San Francisco, San Francisco, California.
authors.forename: Marc
authors.initials: M
authors.lastname: Mabray
authors.affiliation: Department of Radiation Oncology, University of California - San Francisco, San Francisco, California.
authors.forename: William
authors.initials: W
authors.lastname: Silveira
authors.affiliation: Department of Radiology, University of California - San Francisco, San Francisco, California.
authors.forename: Peter Y
authors.initials: PY
authors.lastname: Shen
authors.affiliation: Department of Otolaryngology, Head and Neck Surgery, Division of Head and Neck Oncologic Surgery, University of California - San Francisco, San Francisco, California.
authors.forename: William R
authors.initials: WR
authors.lastname: Ryan
authors.affiliation: Department of Radiology, University of California - San Francisco, San Francisco, California.
authors.forename: Alina
authors.initials: A
authors.lastname: Uzelac
authors.affiliation: Department of Radiation Oncology, University of California - San Francisco, San Francisco, California.|Department of Otolaryngology, Head and Neck Surgery, Division of Head and Neck Oncologic Surgery, University of California - San Francisco, San Francisco, California.
authors.forename: Sue S
authors.identifier: 0000-0002-0779-7476
authors.initials: SS
authors.lastname: Yom
mesh_terms: D000328:Adult; D000368:Aged; D002294:Carcinoma, Squamous Cell / Q000000981:diagnostic imaging* / Q000401:mortality / Q000473:pathology / Q000628:therapy*; D059248:Chemoradiotherapy / Q000379:methods; D015331:Cohort Studies; D016208:Databases, Factual; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D018572:Disease-Free Survival; D055088:Early Detection of Cancer / Q000379:methods; D005260:Female; D006258:Head and Neck Neoplasms / Q000000981:diagnostic imaging* / Q000401:mortality / Q000473:pathology / Q000628:therapy*; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D018365:Neoplasm, Residual / Q000000981:diagnostic imaging* / Q000473:pathology; D009959:Oropharyngeal Neoplasms / Q000000981:diagnostic imaging* / Q000401:mortality / Q000473:pathology / Q000628:therapy*; D000072078:Positron Emission Tomography Computed Tomography / Q000379:methods; D016016:Proportional Hazards Models; D012372:ROC Curve; D015203:Reproducibility of Results; D012189:Retrospective Studies; D018570:Risk Assessment; D000077195:Squamous Cell Carcinoma of Head and Neck; D016019:Survival Analysis
keywords: MRI diffusion-weighted imaging (DWI); chemoradiation; oropharyngeal cancer; positron emission tomography (PET)/CT; surveillance