The Ultracyt Study - is EU-TIRADS Useful in Selecting Nodules for Fine Needle Aspiration Cytology?

Study Overview
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Brief Summary
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This is a randomized study evaluating selective fine-needle aspiration cytology based on structured ultrasound using EU-TIRADS versus non-selective ultrasound guided cytology. Primary outcome is frequency of suspicious cytology (Bethesda III-VI) which is expected to be higher in the selective group compared to the non-selective group. Secondary outcome is the frequency of malignancy which is expected to be equal in both groups. However, the investigators do not expect to reach statistical significance for the secondary outcome according to power calculations.

Detailed Description
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Thyroid nodules are common in the population, and the reported incidence of thyroid cancer is increasing in most parts of the world. Palpable thyroid nodules are reported in 4-5 per cent of the population, of which 5-10 per cent are malignant. The reported incidence of thyroid nodules on ultrasound is higher. EU-TIRADS has been shown in retrospective cohort studies to accurately stratify thyroid nodules with respect to risk of thyroid cancer. EU-TIRADS has been used in Western Sweden since 2017 and in 2021 it was implemented in the Swedish National Guidelines for thyroid cancer. To the knowledge of the investigators, no randomized controlled study has been carried out validating EU-TIRADS. This multicenter regional study aims to investigate the safety of using selective cytology using EU-TIRADS. Primary outcome is the result of cytology suspicious of thyroid cancer. In the selective group, low risk nodules will not undergo cytology and therefore the frequency of cytologically suspicious nodules (Bethesda III-VI) is expected to be higher in this group.

Official Title
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Selective Ultrasound Guided Cytology Using EU-TIRADS Versus Non-selective Ultrasound Guided Cytology for Diagnosing Thyroid Cancer

Conditions
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Thyroid Cancer, Thyroid Nodule

Intervention / Treatment
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* Diagnostic Test: Non-selective cytology


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients referred to ultrasonography of the thyroid due to goiter symtoms or positive findings on FDG-PET Exclusion Criteria: Patients previously examined with ultrasonography of the thyroid Patients who have previously undergone thyroid surgery

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Randomization 1:1 in blocks of 10.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Selective cytology according to EU-TIRADS<br>All thyroid nodules are evaluated according to EU-TIRADS and cytology is performed according to EU-TIRADS criteria. | |
| Active Comparator: Non-selective cytology<br>All thyroid nodules are evaluated according to EU-TIRADS and cytology is performed on all nodules >1 cm. Cytology will also be performed on EU-TIRADS 5-nodules measuring between 0.5 and 1 cm. | Diagnostic Test: Non-selective cytology<br>* All noduleas are evaluated according to EU-TIRADS. Cytology performed on all nodules larger than 1 cm regardless of ultrasonographic features. Nodules 1 cm or smaller evaluated as EU-TIRADS 5 undergo cytologic examination if possible.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Frequency of suspicious cytology (Bethesda III-VI) in each arm. | Fewer nodules in the selective cytology group will most likely undergo fine needle aspiration cytology (FNAC). However, since ultrasonographically benign nodules will not undergo FNAC the frequency of Bethesda III-VI is expected to be higher in the selective cytology group. | Through study completion, up to 18 months. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Frequency of malignancy | The frequency of malignancy is expected to be similar in both groups. Only patients undergoing surgery will be included in this analysis. The investigators do not expect to find statistical significance according to power calculations. | Through study completion, up to 18 months. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Ultrasonography, Cytology, Thyroid Cancer, Thyroid Nodule, Diagnostics