Utility of TL-201 SPECT in clarifying false-positive FDG-PET findings due to osteoradionecrosis in head and neck cancer

Head Neck. 2010 Dec;32(12):1648-54. doi: 10.1002/hed.21377.

Abstract

Background: This study aimed to determine whether Tl-201 single photon emission CT (SPECT) is potentially useful in differentiating false-positive fluorodeoxyglucose positron emission tomography (FDG-PET) findings caused by osteoradionecrosis (ORN) from recurrent head and neck cancer after radiotherapy.

Methods: Five patients were recruited. Dual-phase FDG-PET and dual-phase Tl-201 SPECT were performed for each patient.

Results: All 5 patients proved to have ORN without recurrent cancer. By visual interpretation, the results were 4 positive versus 1 negative for PET, and 4 negative versus 1 positive for Tl-201 SPECT. The Tl-201 SPECT clarified 3 of the 4 false-positive PETs to be ORN. Dual-phase semiquantitative studies showed decreased standardized uptake value (SUV) over time in 3 of the 4 false-positive PETs and decreased lesion/background ratio over time in the false-positive Tl-201 SPECT.

Conclusion: The Tl-201 SPECT may help clarify suspected false-positive FDG uptake caused by ORN. Dual-phase FDG-PET and dual-phase Tl-201 SPECT may also have some value.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Diagnosis, Differential
  • False Positive Reactions
  • Female
  • Fluorodeoxyglucose F18*
  • Humans
  • Male
  • Middle Aged
  • Neoplasm Recurrence, Local
  • Osteoradionecrosis / diagnostic imaging*
  • Otorhinolaryngologic Neoplasms / diagnostic imaging*
  • Otorhinolaryngologic Neoplasms / radiotherapy
  • Positron-Emission Tomography*
  • Radiopharmaceuticals*
  • Thallium Radioisotopes*
  • Tomography, Emission-Computed, Single-Photon*

Substances

  • Radiopharmaceuticals
  • Thallium Radioisotopes
  • Fluorodeoxyglucose F18