Comparison of Empiric Versus Whole-Body/-Blood Clearance Dosimetry-Based Approach to Radioactive Iodine Treatment in Patients with Metastases from Differentiated Thyroid Cancer

J Nucl Med. 2017 May;58(5):717-722. doi: 10.2967/jnumed.116.179606. Epub 2016 Oct 13.


The optimal management of radioactive iodine (RAI) treatment in patients with metastatic thyroid cancer (TC) is still a matter of debate. Methods: We retrospectively analyzed 352 patients with RAI-avid metastatic well-differentiated TC treated with 131I by an empiric fixed activity of 3.7 GBq at Gustave Roussy (GR, n = 231) or by personalized activity (2.7-18.6 GBq) based on whole-body/-blood clearance (WB/BC) dosimetry at Memorial Sloan Kettering Cancer Center (MSKCC, n = 121). The primary endpoint was to compare overall survival (OS) in the 2 groups of patients by log-rank test. Results: Patients received a median cumulative activity of 14.8 GBq at GR and 24.2 GBq at MSKCC (P < 0.0001). The median follow-up after the diagnosis of metastases was 7.2 y (0.4-31 y). Five-year OS was 86.8% and 78.8% for patients treated at GR and at MSKCC, respectively (P < 0.01). However, there was no statistical difference in OS after correction for sex, age at the diagnosis of distant metastases, metastases site, and metastases extension between the 2 centers (P = 0.16). OS at 5 y was 96% and 96% for patients younger than 40 y with micrometastases, 70% and 65% for patients older than 40 y with macrometastases or multiple metastases, and 92% and 87% for younger patients with macrometastases or older patients with micrometastases treated at GR and MSKCC, respectively (P = not significant). Conclusion: Routine use of WB/BC dosimetry without lesional dosimetry provided no OS advantage when compared with empiric fixed RAI activity in the management of thyroid cancer patients with RAI-avid distant metastases.

Keywords: dosimetry; endocrine; oncology; radioactive iodine; radionuclide therapy; thyroid cancer.

Publication types

  • Multicenter Study

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Child
  • Child, Preschool
  • Dose-Response Relationship, Radiation
  • France / epidemiology
  • Humans
  • Iodine Radioisotopes / therapeutic use*
  • Male
  • Metabolic Clearance Rate
  • Middle Aged
  • Neoplasm Metastasis
  • Prevalence
  • Radiation Exposure / statistics & numerical data*
  • Radiopharmaceuticals / therapeutic use
  • Radiotherapy Dosage
  • Radiotherapy, Conformal / mortality*
  • Retrospective Studies
  • Risk Factors
  • Survival Rate
  • Thyroid Neoplasms / mortality*
  • Thyroid Neoplasms / radiotherapy*
  • Treatment Outcome
  • Whole-Body Counting / methods
  • Whole-Body Counting / statistics & numerical data*
  • Young Adult


  • Iodine Radioisotopes
  • Radiopharmaceuticals