Thyroid CancerNCT04495985
CASE 1320: RAI Uptake and Serum Prolactin in Thyroid Cancer
An observational study of Thyroid Cancer, run by The Cleveland Clinic at 1 site in United States.
Trial summary
Radioactive iodine (RAI) is a radioisotope used to ablate thyroid gland remnant after thyroidectomy in patients diagnosed with differentiated thyroid carcinoma (DTC). A whole body scan (WBS) is performed to not only evaluate for iodine uptake by the native thyroid tissue but also to observe for uptake in other areas… Read more about this study
- Who is it for?
- Ages 18 years and older, women only
- Conditions the study is for
- Thyroid Cancer
- How many people
- 39 participants
- Where
- 1 siteUnited States
- Study dates
- 14 Jul 2020to Dec 2026
- Phase
- Observational
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- Women only
- No healthy volunteers
- Adult, Older adult
Study population: Group 1: Female patients with differential thyroid cancer prepared for radioactive iodine whole body scan by withdrawal from thyroid hormones Group 2: Female patients with differential thyroid cancer prepared for radioactive iodine whole body scan by rh-TSH.
Who may be able to join
- Female patients with diagnosis of differentiated thyroid carcinoma who have had thyroidectomy performed previously
- Patients able to understand and sign informed consent for imaging
- Patients already scheduled to undergo radioactive iodine whole body scanning (RAI WBS)
Who cannot join
- Males
- Patients with a history of breast cancer
- Patients with a known history of hyperprolactinemia
- Patients receiving medications known to raise serum prolactin
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Breast Uptake on Radioiodine Scan and Serum Prolactin in Thyroid Cancer Patients Prepared by Thyroid Hormone Withdrawal or Recombinant Human Thyrotropin: A Prospective Study
Radioactive iodine (RAI) is a radioisotope used to ablate thyroid gland remnant after thyroidectomy in patients diagnosed with differentiated thyroid carcinoma (DTC). A whole body scan (WBS) is performed to not only evaluate for iodine uptake by the native thyroid tissue but also to observe for uptake in other areas of the body, which could be physiological or indicative of iodide-avid metastases. Research has shown a correlation between breast cancer and thyroid cancer. Patients with DTC have been found to have elevated levels of serum prolactin, which could lead to mammary gland dysfunction.
In patients with DTC undergoing RAI scanning or therapy, it has been previously observed that patients prepared by thyroid hormone withdrawal have significantly higher breast uptake on whole body scan compared to those prepared by rh-TSH. Considering the impact of prolactin on breast tissue, this study aims to correlate these findings with the lab values and the method of preparation.
Accordingly, the research question is as follows: does the method of WBS preparation impact prolactin levels and how does that correlate with breast uptake in patients with DTC undergoing RAI WBS?
Read the detailed description
Radioactive iodine (RAI) is a radioisotope used to ablate thyroid gland remnant after thyroidectomy in patients diagnosed with differentiated thyroid carcinoma (DTC). A whole body scan (WBS) is performed to not only evaluate for iodine uptake by the native thyroid tissue but also to observe for uptake in other areas of the body, which could be physiological or indicative of iodide-avid metastases. Research has shown a correlation between breast cancer and thyroid cancer. Patients with DTC have been found to have elevated levels of serum prolactin, which could lead to mammary gland dysfunction. As such, this study will evaluate for breast uptake on the RAI WBS. Research has shown that patients with DTC may have uptake on RAI WBS.
There is a concern in the molecular imaging community and oncology community that increased I-131 retention in breast tissue may increase the risk of future breast malignancy. The notion that increased serum prolactin concentration increases iodine uptake in breast tissue comes mostly from case series. A correlation between high prolactin as a result of withdrawal from thyroid hormone treatment vs stimulation by recombinant human thyrotropin and uptake by thyroid tissue is the main research question. This research will not be able to answer the question of whether such breast uptake is associated with the future risk breast malignancy. The later research question should be undertaken by other researchers in a larger study with longer follow up. Metastases to the breast from thyroid cancer are rare. Uptake in a discrete lesion in the breast will need to be investigated. It is unclear whether breast adenocarcinoma will concentrate iodine.
In a previous retrospective study of 194 patients with DTC and no breast cancer, it was demonstrated that patients prepared by withdrawal from thyroid hormone had 5-fold higher peak I-131 uptake in breast tissue on post-therapy scan compared to patients prepared by recombinant human thyrotropin (rh-TSH). In other research, DTC patients with hyperprolactinemia have been found to have increased uptake by the mammary gland. The hypothesis is that patients prepared by withdrawal would have increased serum prolactin compared to patients prepared by rh-TSH who are not made hypothyroid. This study plans to prospectively evaluate serum prolactin and breast uptake on the RAI WBS and assess the impact of pre-scan preparation on those variables. This would be the first prospective study of its kind in this set of patients to look at whether the method of pre-RAI scan preparation might impact RAI uptake with correlation to prolactin levels.
- Conditions
- Thyroid Cancer
- Medical subject headings
- Thyroid Neoplasms
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
| Study group | Role | What they receive |
|---|---|---|
| Thyrogen (rh-TSH) | Group 1: Female patients prepared for radioactive iodine treatment by rh-TSH (Thyrogen) | |
| Withdrawal from thyroid hormone | Group 2: Female patients prepared for radioactive iodine treatment by withdrawal from thyroid hormones |
What is being measured
The primary outcome is the main question the study is designed to answer.
Breast uptake of I-131 on whole body radioactive iodine scan
Breast uptake of I-131 on whole body radioactive iodine scan
Measured: 10 days after treatment
Secondary outcomes (4)
Change in serum prolactin concentration
Change in prolactin levels in thyroid hormone withdrawal group
Measured: 6 weeks
Serum prolactin concentration
Change in prolactin levels in thyrogen preparation group
Measured: 3 days
Prolactin level and breast uptake of I-131
Correlation between serum prolactin level and breast uptake of I-131
Measured: Day 46 of thyroid hormone withdrawal group
Prolactin level and breast uptake of I-131
Correlation between serum prolactin level and breast uptake of I-131
Measured: Day 26 of thyrogen preparation group
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted3 Aug 2020
- Study start14 Jul 2020
- Primary completion27 Jul 2022
- Study completionDec 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Thyroid CancerStudies of the same condition, open and under way.
- More trials run by The Cleveland ClinicThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 39 participants (actual)
Sponsor and investigators
- Lead sponsor
- The Cleveland Clinic
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
- Investigators
- Alexandra Mikhael, MD, Principal investigator, The Cleveland Clinic
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04495985
- Sponsor's protocol ID
- IRB 20-488
- Status last verified
- Jan 2026
- First submitted
- 10 Jun 2020
- Last updated
- 28 Jan 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 28 Jan 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Breast Uptake on Radioiodine Scan and Serum Prolactin in Thyroid Cancer Patients Prepared by Thyroid Hormone Withdrawal or Recombinant Human Thyrotropin: A Prospective Study
- ClinicalTrials.gov ID
- NCT04495985
- Acronym / sponsor ID
- IRB 20-488
- Conditions
- Thyroid Cancer
- Study type
- Observational
- Recruitment status
- Active, not recruiting
- Enrolment
- 39 participants (actual)
- Lead sponsor
- The Cleveland ClinicUniversity, hospital or other
- Study start
- 14 Jul 2020 (actual)
- Primary completion
- 27 Jul 2022 (actual)
- Study completion
- Dec 2026 (estimated)
- First posted
- 3 Aug 2020 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Radioactive iodine (RAI) is a radioisotope used to ablate thyroid gland remnant after thyroidectomy in patients diagnosed with differentiated thyroid carcinoma (DTC). A whole body scan (WBS) is performed to not only evaluate for iodine uptake by the native thyroid tissue but also to observe for uptake in other areas of the body, which could be physiological or indicative of iodide-avid metastases. Research has shown a correlation between breast cancer and thyroid cancer. Patients with DTC have been found to have elevated levels of serum prolactin, which could lead to mammary gland dysfunction.
In patients with DTC undergoing RAI scanning or therapy, it has been previously observed that patients prepared by thyroid hormone withdrawal have significantly higher breast uptake on whole body scan compared to those prepared by rh-TSH. Considering the impact of prolactin on breast tissue, this study aims to correlate these findings with the lab values and the method of preparation.
Accordingly, the research question is as follows: does the method of WBS preparation impact prolactin levels and how does that correlate with breast uptake in patients with DTC undergoing RAI WBS?
Detailed description
Radioactive iodine (RAI) is a radioisotope used to ablate thyroid gland remnant after thyroidectomy in patients diagnosed with differentiated thyroid carcinoma (DTC). A whole body scan (WBS) is performed to not only evaluate for iodine uptake by the native thyroid tissue but also to observe for uptake in other areas of the body, which could be physiological or indicative of iodide-avid metastases. Research has shown a correlation between breast cancer and thyroid cancer. Patients with DTC have been found to have elevated levels of serum prolactin, which could lead to mammary gland dysfunction. As such, this study will evaluate for breast uptake on the RAI WBS. Research has shown that patients with DTC may have uptake on RAI WBS.
There is a concern in the molecular imaging community and oncology community that increased I-131 retention in breast tissue may increase the risk of future breast malignancy. The notion that increased serum prolactin concentration increases iodine uptake in breast tissue comes mostly from case series. A correlation between high prolactin as a result of withdrawal from thyroid hormone treatment vs stimulation by recombinant human thyrotropin and uptake by thyroid tissue is the main research question. This research will not be able to answer the question of whether such breast uptake is associated with the future risk breast malignancy. The later research question should be undertaken by other researchers in a larger study with longer follow up. Metastases to the breast from thyroid cancer are rare. Uptake in a discrete lesion in the breast will need to be investigated. It is unclear whether breast adenocarcinoma will concentrate iodine.
In a previous retrospective study of 194 patients with DTC and no breast cancer, it was demonstrated that patients prepared by withdrawal from thyroid hormone had 5-fold higher peak I-131 uptake in breast tissue on post-therapy scan compared to patients prepared by recombinant human thyrotropin (rh-TSH). In other research, DTC patients with hyperprolactinemia have been found to have increased uptake by the mammary gland. The hypothesis is that patients prepared by withdrawal would have increased serum prolactin compared to patients prepared by rh-TSH who are not made hypothyroid. This study plans to prospectively evaluate serum prolactin and breast uptake on the RAI WBS and assess the impact of pre-scan preparation on those variables. This would be the first prospective study of its kind in this set of patients to look at whether the method of pre-RAI scan preparation might impact RAI uptake with correlation to prolactin levels.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Thyrogen (rh-TSH) | – | –Group 1: Female patients prepared for radioactive iodine treatment by rh-TSH (Thyrogen) |
| Withdrawal from thyroid hormone | – | –Group 2: Female patients prepared for radioactive iodine treatment by withdrawal from thyroid hormones |
Who may qualify
- Ages
- 18 years and older
- Sex
- Female only
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- Group 1: Female patients with differential thyroid cancer prepared for radioactive iodine whole body scan by withdrawal from thyroid hormones Group 2: Female patients with differential thyroid cancer prepared for radioactive iodine whole body scan by rh-TSH.
Key inclusion criteria (3 listed)
- Female patients with diagnosis of differentiated thyroid carcinoma who have had thyroidectomy performed previously
- Patients able to understand and sign informed consent for imaging
- Patients already scheduled to undergo radioactive iodine whole body scanning (RAI WBS)
Key exclusion criteria (4 listed)
- Males
- Patients with a history of breast cancer
- Patients with a known history of hyperprolactinemia
- Patients receiving medications known to raise serum prolactin
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Primary outcome
Breast uptake of I-131 on whole body radioactive iodine scan
Time frame: 10 days after treatment
Breast uptake of I-131 on whole body radioactive iodine scan
4 secondary outcomes
Change in serum prolactin concentration
Time frame: 6 weeks
Serum prolactin concentration
Time frame: 3 days
Prolactin level and breast uptake of I-131
Time frame: Day 46 of thyroid hormone withdrawal group
Prolactin level and breast uptake of I-131
Time frame: Day 26 of thyrogen preparation group
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 28 Jan 2026.
- Individual participant dataSharing planned: No
Related trials for Thyroid Cancer
Recruiting
NIRAF-Guided Parathyroid Identification During Thyroidectomy
Hypocalcemia, Hypoparathyroidism
Active, not recruitingPhase 1
Prospective Exploratory Study of FAPi PET/CT With Histopathology Validation in Patients With Various Cancers
Bladder Carcinoma, Cervical Carcinoma
Not yet recruitingPhase 1/2
177Lu-DOTA-EB-TATE in Adult Patients With Metastatic, Radioactive Iodine Non-Responsive Oncocytic (Hurthle-Cell) Thyroid Cancer
Thyroid Cancer
RecruitingObservational study
DICER1-related Pleuropulmonary Blastoma Cancer Predisposition Syndrome: A Natural History Study
Pleuropulmonary Blastoma, Cystic Nephroma
Recruiting
Evaluation of DNA Methylation Signatures for the Diagnosis and Management of Thyroid Nodules
Thyroid Gland Carcinoma
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Alexandra Mikhael, MD principal investigator
The Cleveland Clinic
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Thyroid Cancer, run by The Cleveland Clinic at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 3 inclusion and 4 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: under way, not looking for participants, as of the sponsor's last update on 28 Jan 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Breast uptake of I-131 on whole body radioactive iodine scan (time frame: 10 days after treatment). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 28 Jan 2026.