The Dose of Radioactive Iodine Needed to Ablate the Thyroid Remnant Left Behind After Thyroidectomy

The recruitment status of this study is unknown because the information has not been verified recently.
Verified December 1999 by Helsinki University.
Recruitment status was  Active, not recruiting
Sponsor:
Information provided by:
Helsinki University
ClinicalTrials.gov Identifier:
NCT00115895
First received: June 26, 2005
Last updated: August 2, 2005
Last verified: December 1999
  Purpose

The thyroid cells take up iodine, and radioactive iodine is commonly used to irradiate residual thyroid tissue and thyroid cancer following surgical removal of the thyroid gland (thyroidectomy). A whole body radioactive iodine scanning is usually carried out after thyroidectomy to assess the amount of thyroid tissue left behind at surgery (that might still contain cancer), and to evaluate the presence of iodine avid lesions elsewhere in the body (that might be cancer metastases). A large dose of radioactive iodine is often given, still the optimal iodine dose to ablate the thyroid remnant after surgery is not known. In this study, two radioactive iodine doses are compared in the ablation of the thyroid remnant, a smaller (1110 MBq) dose and a larger (3700 MBq) dose. The study participants are randomly allocated using a 1:1 ratio to receive either the smaller or the larger radioactive iodine dose. These treatments are compared for safety, adverse effects, and the need for subsequent repeat treatments. The individual absorbed radiation doses are measured. The study hypothesis is that fewer repeat radioiodine treatments might be needed after the larger dose, but the larger dose might be associated with a higher frequency of adverse events.


Condition Intervention Phase
Thyroid Neoplasms
Drug: radioiodine
Phase 3

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Parallel Assignment
Masking: Open Label
Primary Purpose: Treatment
Official Title: Effect of the Radioiodine Dose in Thyroid Ablation- A Randomized Comparison of 1110 MBq to 3700 MBq

Resource links provided by NLM:


Further study details as provided by Helsinki University:

Primary Outcome Measures:
  • Cumulative number of radioactive iodine administrations

Secondary Outcome Measures:
  • Adverse events
  • Absorbed radiation dose
  • Cancer recurrence

Estimated Enrollment: 160
Study Start Date: January 2000
Estimated Study Completion Date: September 2005
Detailed Description:

The study participants are randomly allocated to receive either a 1110 MBq or a 3700 MBq dose of radioiodine (131I) approximately 5 weeks after thyroidectomy. Thyroxin substitution is initiated only after administration of radioactive iodine. Treatment efficacy is monitored using serum thyroglobulin measurements and whole body radioiodine scanning. The absorbed radiation dose at the thyroid remnant and the biological half-life of radioactive iodine are measured with SPECT, 131I iodine detector and a Geiger counter.

Treatment related adverse events are collected using structured forms 4 to 5 days, 2 weeks and 3 months after administration of radioiodine. The need for a repeat treatment is assessed 4 to 6 months after the first administration of radioiodine. The criteria for a repeat radioiodine treatment are serum thyroglobulin > 1 ug/L and/or presence of abnormal radioiodine uptake in a whole body radioiodine scanning, which is carried out following a 4-week interruption of thyroxin supplementation or following administration of rhTSH.

Number of patients: 160

Aims of the study:

  • To find out weather the risk for second radioiodine treatment differs with two dose levels of radioiodine: 1110 MBq or 3700 MBq.
  • To study possible differences in the adverse effects in the treatment groups. Also days at hospital are counted.
  • To analyse the effect of absorbed radiation dose to the treatment results
  Eligibility

Ages Eligible for Study:   18 Years and older
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Criteria

Inclusion criteria:

  • Total or near total thyroidectomy performed for papillary or follicular thyroid cancer
  • R0-1 resection, no macroscopic cancer left behind at surgery
  • Physically and emotionally able to undergo radioiodine treatment
  • A written informed consent

Exclusion criteria:

  • Pregnancy
  • Physical or psychiatric illness that may deteriorate during the isolation period required by radioiodine therapy
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT00115895

Locations
Finland
Helsinki University Central Hospital, Department of Oncology
Helsinki, Finland, FIN-00029HUS
Sponsors and Collaborators
Helsinki University
Investigators
Principal Investigator: Hanna O Mäenpää, M.D. Ph.D. Deputy Chief Physician
  More Information

Additional Information:
Publications:
Additional publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
ClinicalTrials.gov Identifier: NCT00115895     History of Changes
Other Study ID Numbers: SYTJ001T/2000
Study First Received: June 26, 2005
Last Updated: August 2, 2005
Health Authority: Finland: Ethics Committee

Keywords provided by Helsinki University:
radioiodine
serum thyroglobulin
whole body radioiodine scanning

Additional relevant MeSH terms:
Thyroid Diseases
Thyroid Neoplasms
Endocrine System Diseases
Endocrine Gland Neoplasms
Neoplasms by Site
Neoplasms
Head and Neck Neoplasms

ClinicalTrials.gov processed this record on September 18, 2014