Home › Trials › NCT04290663

Comparing two methods of radioiodine treatment for thyroid cancer

Multicentric Phase III Trial Comparing Two Strategies in Intermediate-risk Differentiated Thyroid Cancer Patients: Systematic Radioiodine Administration Versus Decision of Radioiodine Treatment Guided by a Post-operative Work-up Based on Serum Tg Values and Diagnostic RAI Scintigraphy

Phase 3 Interventional Centre Francois Baclesse · NCT04290663

This study is testing two different ways to give radioiodine treatment to people with thyroid cancer to see which method works better for them after surgery.

Quick facts

PhasePhase 3
Study typeInterventional
Enrollment476 (estimated)
Ages18 Years and up
SexAll
SponsorCentre Francois Baclesse Academic / other
Locations29 sites (Pointe à Pitre, Guadeloupe and 28 other locations)
Trial IDNCT04290663 on ClinicalTrials.gov

What this trial studies

This trial evaluates two different strategies for administering radioiodine treatment in patients with intermediate-risk differentiated thyroid cancer. One approach involves systematic administration of radioiodine, while the other relies on a post-operative assessment based on serum thyroglobulin levels and diagnostic RAI scintigraphy to guide treatment decisions. The study aims to determine which method is more effective in managing this patient population. Participants will be randomly assigned to one of the two treatment strategies following total thyroidectomy.

Who should consider this trial

Good fit: Ideal candidates are patients with differentiated thyroid cancer classified as intermediate-risk according to specific TNM criteria, who have undergone total thyroidectomy.

Not a fit: Patients with aggressive subtypes of thyroid cancer or those with known distant metastases may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could optimize radioiodine treatment protocols, leading to better outcomes for patients with intermediate-risk thyroid cancer.

How similar studies have performed: Other studies have explored radioiodine treatment strategies, but this specific comparison of systematic versus guided treatment is novel.

Eligibility criteria

Show full inclusion / exclusion criteria 
Inclusion Criteria:

* Subgroup of patients with differentiated thyroid cancer and intermediate-risk defined as follows according to TNM 2017:

  * Papillary thyroid cancer (PTC) without aggressive subtype, follicular thyroid cancer (FTC) (with \< 4 foci of vascular invasion) or Hürthle cell carcinoma (HCC)
  * T1b or T2 with minimal extra-thyroid extension into the perithyroidal soft tissues and/or pN1 with largest nodal dimension between 2 and 10 mm, without extra-capsular invasion and with a number of metastatic nodes ≤ 10
  * T1aN1 with largest nodal dimension between 2 and 10 mm, without extra-capsular invasion and with a number of metastatic nodes ≤ 10
* Patient treated by total thyroidectomy with macroscopically complete tumor resection (R0 or R1) ± neck dissection
* Total thyroidectomy performed within 6 to 14 10 weeks before randomization
* Patient with or without anti-thyroglobulin antibodies (TgAb)
* No known distant metastases
* Normal post-operative neck ultrasound (US) or if doubtful US, negative cytology and normal Tg value (\<10 ng/ml) in FNA washout fluid
* Post-operative LT4 treatment initiated at least 6 weeks before randomization
* Performance Status 0 or 1
* Patients aged 18 years or older
* Signed informed consent form
* Patient who agrees to be followed annually during 5 years
* Patient affiliated to the French social security system

Exclusion Criteria:

* • Patients with:

  * medullary or anaplastic thyroid cancer
  * or poorly differentiated carcinoma
  * or well differentiated FTC with at least more than 4 foci of vascular invasion
  * or PTC with aggressive variants (tall cell or columnar cell carcinoma, diffuse sclerosing papillary, hobnail variant)
  * NIFTP (Noninvasive follicular thyroid neoplasm with papillary-like nuclear features)

    • Low-risk or high-risk DTC patients according to ATA 2015, and intermediate-risk patients with extra-thyroid extension into the perithyroidal muscles (pT3b according to pTNM 2017), and/or pN1 with nodal largest dimension \>10 mm or with extra-capsular invasion or more than 10 metastatic nodes. This excludes the following patients:
  * All pT1a, pT3 or pT4
  * pT1aN0/x with or without minimal extra-thyroid extension
  * pT1bN0/x, pT2N0/Nx without minimal extra-thyroid extension
  * pT1aN1 or pT1bN1 or pT2N1 without extra-thyroid extension and with nodal largest dimension \<2mm
  * pT1aN1 or pT1bN1 or pT2N1 without extra-thyroid extension and with nodal largest dimension \>10mm
  * pT2N0/Nx without extra-thyroid extension
  * pT2N1 without extra-thyroid extension and with nodal largest dimension \<2mm
  * pT2N1 without extra-thyroid extension and with nodal largest dimension \>10mm
  * Surgery considered as macroscopically incomplete (R2)

    * Patients who have undergone lobectomy only
    * Post-operative neck US with metastatic lymph-nodes confirmed by cytology or by increased Tg (\>10 ng/ml) in FNA washout fluid
    * Drugs affecting thyroid function including iodinated contrast agents in the 6 weeks prior to randomization. Amiodarone should have been stopped at least 1 year before randomization.
    * Previous RAI treatment for thyroid cancer
    * Pregnant or lactating women
    * Any associated geographical, social or psychopathological condition that could compromise the patient's ability to participate in the study
    * Patient deprived of liberty or placed under the authority of a tutor
    * History of malignancy in the past 3 years, except skin cancer excluding melanoma, carcinoma in situ of the cervix. Any other solid tumor or lymphoma (without bone marrow involvement) must have been treated and not have shown signs of recurrence for at least 3 years

Where this trial is running

Pointe à Pitre, Guadeloupe and 28 other locations

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.
View on ClinicalTrials.gov → Find more trials like this →
Conditions Thyroid CancerIntermediate RiskradioiodineI131
Last reviewed 2026-06-13 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.