The Dose of Radioactive Iodine Needed to Ablate the Thyroid Remnant Left Behind After Thyroidectomy
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ClinicalTrials.gov Identifier: NCT00115895 |
Recruitment Status : Unknown
Verified March 2018 by Hanna Mäenpää, University of Helsinki.
Recruitment status was: Active, not recruiting
First Posted : June 27, 2005
Last Update Posted : March 2, 2018
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Condition or disease | Intervention/treatment | Phase |
---|---|---|
Thyroid Neoplasms | Drug: Radioactive iodine | Phase 3 |
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
Study Type : | Interventional (Clinical Trial) |
Actual Enrollment : | 160 participants |
Allocation: | Randomized |
Intervention Model: | Parallel Assignment |
Masking: | None (Open Label) |
Primary Purpose: | Treatment |
Official Title: | Effect of the Radioiodine Dose in Thyroid Ablation- A Randomized Comparison of 1110 MBq to 3700 MBq |
Study Start Date : | January 2000 |
Actual Primary Completion Date : | October 2004 |
Estimated Study Completion Date : | September 2020 |
Arm | Intervention/treatment |
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Experimental: Radioactive iodine 1,1 GBq
Low activity of radioiodine, 1,1 GBq
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Drug: Radioactive iodine
Radioiodine is radionuclear treatment given in oral capsules in two activies 1,1 and 3,7 GBq
Other Name: radioiodine |
Radioactive iodine 3,7 GBq
Routine activity of radioiodine, 3,7 GBq
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Drug: Radioactive iodine
Radioiodine is radionuclear treatment given in oral capsules in two activies 1,1 and 3,7 GBq
Other Name: radioiodine |
- Cumulative number of radioactive iodine administrations [ Time Frame: 15 yrs ]
- Adverse events [ Time Frame: 15 yrs ]
- Absorbed radiation dose [ Time Frame: 15 yrs ]
- Cancer recurrence [ Time Frame: 15 yrs ]

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Ages Eligible for Study: | 18 Years and older (Adult, Older Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
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

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00115895
Finland | |
Helsinki University Central Hospital, Department of Oncology | |
Helsinki, Finland, FIN-00029HUS |
Principal Investigator: | Hanna O Mäenpää, M.D. Ph.D. | Deputy Chief Physician |
Publications:
Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Responsible Party: | Hanna Mäenpää, Chief of Department, University of Helsinki |
ClinicalTrials.gov Identifier: | NCT00115895 |
Other Study ID Numbers: |
SYTJ001T/2000 |
First Posted: | June 27, 2005 Key Record Dates |
Last Update Posted: | March 2, 2018 |
Last Verified: | March 2018 |
radioiodine serum thyroglobulin whole body radioiodine scanning |
Thyroid Neoplasms Thyroid Diseases Endocrine System Diseases Endocrine Gland Neoplasms |
Neoplasms by Site Neoplasms Head and Neck Neoplasms |