Comparison of I-124 PET/CT, F-18 FDG PET/CT & I-123 Whole Body Scintigraphy for Recurrent Thyroid CA

• Evaluating I-124 as a PET/CT radiotracer
• Evaluating the imaging protocol that combines I-124 PET/CT and F-18 FDG PET/CT.

The management of thyroid cancer patients with suspicion of recurrent disease based on rising/detectable levels of thyroglobulin (Tg) involves imaging with iodine-123 whole body scintigraphy (I-123 WBS) and F-18 FDG PET/CT. However, the disease is not always detected. The use of another iodine isotope (I-124) with positron emitting characteristics for PET/CT may allow better identification of recurrent disease, thus allowing for more patients to be treated with I-131 as a curative attempt.

The management of thyroid cancer patients with suspicion of recurrent disease based on rising/detectable levels of thyroglobulin (Tg) involves imaging with iodine-123 whole body scintigraphy (I-123 WBS) and F-18 FDG PET/CT. However, the disease is not always detected. The use of another iodine isotope (I-124) with positron emitting characteristics for PET/CT may allow better identification of recurrent disease, thus allowing for more patients to be treated with I-131 as a curative attempt.

Conducting this study we hope to find whether I-124 PET/CT allows for detection of more lesions in patients with suspected recurrent thyroid cancer than the current standard of care represented by I-123 WBS and F-18 FDG PET/CT.

Participants with Thyroid cancer

• Drug: Iodine-124
  2 mCi, oral
  Other Name: Eastern Isotopes
• Drug: Iodine-123
  2 mCi, oral
  Other Name: MDS Nordion
• Drug: F-18 FDG
  10-15 mCi, iv
  Other Names:

  • Fludeoxyglucose (18 F)
  • fluorodeoxyglucose (18 F)
  • MIPS

Inclusion Criteria:- Patient at Nuclear Medicine clinic at Stanford University Medical Center

• Treated thyroid cancer.
• Detectable levels of Tg.
• Referred for I-123 WBS and F-18 FDG PET/CT for detection of recurrent thyroid cancer.
• Able to have a I-124 PET/CT the day after I-123 WBS and F-18 FDG PET/CT
• Patients older than 18-year-old.
• Patients with history of treated thyroid cancer and suspected recurrent thyroid cancer based on detectable levels of Tg.
• Patients must have I-123 WBS and F-18 FDG PET/CT performed prior to the I-124 PET/CT.
• Patients must understand and voluntarily sign an Informed Consent form after the contents have been fully explained to them.

Exclusion Criteria:- Patients who are not eligible for I-123 WBS and F-18 FDG PET/CT.

• Patients who cannot complete I-123 WBS and F-18 FDG PET/CT.
• Pregnant women.
• Healthy volunteers.
• Patients participating in other research studies.