Using advanced imaging to improve treatment for thyroid cancer

The Use of 124-I-PET/CT Whole Body and Lesional Dosimetry in Differentiated Thyroid Cancer

Phase 2 Interventional National Institutes of Health Clinical Center (CC) · NCT03841617

This study is testing a new imaging method to see if it can help doctors give the right amount of radioactive iodine treatment to people with high-risk thyroid cancer.

Quick facts

PhasePhase 2
Study typeInterventional
Enrollment30 (estimated)
Ages18 Years to 90 Years
SexAll
SponsorNational Institutes of Health Clinical Center (CC) NIH
Drugs / interventionsselumetinib, radiation
Locations1 site (Bethesda, Maryland)
Trial IDNCT03841617 on ClinicalTrials.gov

What this trial studies

This study evaluates the use of 124-I-PET/CT imaging to calculate dosimetry for patients with differentiated thyroid cancer (DTC) who are at high risk for metastases. Participants will undergo two methods of thyroid stimulating hormone (TSH) stimulation and receive treatment based on dosimetric calculations to determine the maximum safe dosage of radioactive iodine (RAI). The primary objective is to compare the dosimetry results from 124-I-PET/CT with traditional methods, while secondary objectives include assessing the early response to therapy based on predicted tumor uptake. This approach aims to enhance the effectiveness of treatment for patients with metastatic thyroid cancer.

Who should consider this trial

Good fit: Ideal candidates include patients with a confirmed diagnosis of differentiated thyroid cancer who have undergone total thyroidectomy and present with persistent or recurrent disease.

Not a fit: Patients with thyroid cancer that is not RAI-avid or those without evidence of persistent or recurrent disease may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could lead to more personalized and effective treatment plans for patients with differentiated thyroid cancer.

How similar studies have performed: While the use of dosimetry in thyroid cancer treatment is established, the specific application of 124-I-PET/CT for this purpose is novel and has not been extensively tested in prior studies.

Eligibility criteria

Show full inclusion / exclusion criteria
* INCLUSION CRITERIA:
* Patients with established thyroid cancer diagnosis based on the pathology report reviewed at the National Institutes of Health, who:

  * underwent total thyroidectomy plus or minus neck lymph node dissection as clinically indicated,
  * are presenting with known per structural imaging (US neck, CT or MRI neck/chest/abdomen/pelvis) persistent/recurrent disease either locally advanced or presenting with distant metastases; or
  * are presenting with suspected persistent/recurrent locoregional or distant metastases based on the high risk features such as advanced tumor per pathology report (tumor size \>4 cm, exrathyroidal extension, higher risk pathology such as tall cell, columnar cell, poorly differentiated variant, follicular thyroid cancer with gross vascular invasion, positive margins after the surgery, bulky lymphadenopathy in the central and/or lateral neck), detectable/increasing baseline/suppressed thyroglobulin (Tg) level or detectable/increasing anti-Tg antibody titers if anti-Tg antibodies are present.
  * are either RAI -naive or requiring repeated RAI therapy for locally advanced disease or distant metastases or underwent therapy with BRAF inhibitor (dabrafenib or vemurafenib\*) or selumetinib\*\* for at least 4 weeks that may re-induce RAI uptake.
  * Underwent imaging with either a CT or MRI of the brain and spine with gadolinium contrast to screen for the brain/spine metastases.

    * Age greater than or equal to 18 years of age.
    * 24 hour urine iodine excretion of less than or equal to 150 micro grams/24 hour.

      * BRAF inhibitors are recommended by 2021 NCCN guidelines as one of the management options for BRAF mutant tumors(13,14)

        * Selumetinib has an FDA orphan drug designation for adjuvant treatment of metastatic thyroid cancer to re-induce RAI uptake

EXCLUSION CRITERIA:

-Patients with RAI-non avid disease documented by negative post-therapy whole body scans performed after previous RAI treatments and not subjected to re-differentiation therapy.

* Serious underlying medical conditions that restrict diagnostic testing or therapy such as renal failure, congestive cardiac failure or active coexisting non-thyroid carcinoma, severe depression which might be exacerbated by thyroid hormone withdrawal.
* Patients with spinal or brain metastases as they are at risk of TSH-stimulation induced swelling of metastatic lesions leading to potentially detrimental side effects. These patients will be evaluated per the standard of care protocol 77-DK-0096.

  * Pregnant or lactating women per self report.
  * Adults who are incapable of providing informed consent.

Where this trial is running

Bethesda, Maryland

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Thyroid CancerPET/CT124-IRadioiodineMetastases
Last reviewed 2026-06-09 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.