European Archives of Oto-Rhino-Laryngology

, Volume 274, Issue 2, pp 1015–1019 | Cite as

Cervical lymph node metastases of squamous cell carcinoma of unknown origin: the diagnostic value of FDG PET/CT and clinical outcome

  • Einar Dale
  • Jon M. Moan
  • Terje A. Osnes
  • Trond V. Bogsrud
Head and Neck


FDG PET/CT is perceived as a valuable diagnostic tool in addition to the standard diagnostic workup for patients with isolated neck lymph nodes of squamous cell carcinoma of unknown primary (SCCUP). For patients with SCCUP intended for primary radiotherapy, we hypothesize that the previously reported FDG PET/CT detection rates are too high. From 2008 to 2015, 30 SCCUP patients were examined with FDG PET/CT. The objective of the FDG PET/CT examination was twofold: (1) improve the radiotherapy target definition, and (2) identify the primary cancer. Before the FDG PET/CT, the patients had been through a standard workup consisting of CT of the neck and chest, examination with flexible endoscopy with patient awake, panendoscopy and examination under general anesthesia, tonsillectomy and sometimes blind sampling biopsies, and MRI (floor of the mouth). All FDG PET/CTs were performed applying a flat table, head support and fixation mask as part of the radiotherapy treatment planning. Diagnostic CT with contrast was an integrated part of the PET/CT examination. Only 1/30 patients (cancer of the vallecula) had their primary cancer detected by FDG PET/CT. In addition, a non-biopsied patient with high uptake in the ipsilateral palatine tonsil was included, giving a detection rate of ≤7 % (95 % CI 2–21 %). In this retrospective study, we found that the FDG PET/CT detection rate of the primary for SCCUP patients is lower than previously reported. It is questionable whether FDG PET/CT is necessary for these patients when improved, advanced workup is available.


Positron emission tomography 18F-FDG Cervical lymph node metastases Head and neck cancer Cancer of unknown primary 


Compliance with ethical standards

This work was funded by a clinical short-term fellowship grant from the Norwegian Cancer Society (Grant Number 160907-2014).

Conflict of interest

All authors declare that they have no conflict of interest.

This study was approved by the institutional research committee as well as the hospital’s patient privacy ombudsman. Informed consent from the patients was not necessary according to Norwegian legislation and approval statement from the hospital’s patient privacy ombudsman.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2016

Authors and Affiliations

  1. 1.Department of OncologyOslo University HospitalOsloNorway
  2. 2.Department of Otorhinolaryngology, Head and Neck SurgeryOslo University HospitalOsloNorway
  3. 3.Department of Radiology and Nuclear MedicineOslo University HospitalOsloNorway

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