Optimal timing of first posttreatment FDG PET/CT in head and neck squamous cell carcinoma

Head Neck. 2016 Apr;38 Suppl 1:E853-8. doi: 10.1002/hed.24112. Epub 2015 Jul 18.


Background: The optimal timing for the initial posttreatment fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT scan after definitive treatment of head and neck squamous cell carcinoma (HNSCC) is unclear.

Methods: We conducted a retrospective review of 247 patients with definitively treated nonmetastatic HNSCC. First posttreatment PET/CT scans were grouped into: <7 weeks, 7 to 10 weeks, 11 to 14 weeks, and ≥15 weeks. Scans were categorized as positive or negative and accuracy of scans was calculated for each group using biopsy, subsequent imaging, or clinical follow-up for 1 year after treatment as a reference standard.

Results: Sixty-seven of the 247 patients (27.1%) had treatment failure. Scans performed at <7 weeks were less accurate than all other time intervals (p < .05). Scans performed at all other intervals were similar in accuracy.

Conclusion: First posttreatment PET/CT can be obtained as early as 2 months after therapy. Scans performed earlier than 2 months have lower accuracy. © 2015 Wiley Periodicals, Inc. Head Neck 38: E853-E858, 2016.

Keywords: fluorodeoxyglucose (FDG); head and neck squamous cell carcinoma; positron emission tomography (PET)/CT; posttreatment; timing.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Carcinoma, Squamous Cell / diagnostic imaging*
  • Carcinoma, Squamous Cell / therapy
  • Female
  • Fluorodeoxyglucose F18
  • Head and Neck Neoplasms / diagnostic imaging*
  • Head and Neck Neoplasms / therapy
  • Humans
  • Male
  • Middle Aged
  • Positron Emission Tomography Computed Tomography*
  • Retrospective Studies
  • Time Factors
  • Tomography, X-Ray Computed
  • Treatment Failure
  • Young Adult


  • Fluorodeoxyglucose F18