Reduced Contrast Administration in Contrast-enhanced Spectral Mammography (CESM)

Study Overview
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Brief Summary
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The optimal dose of iodine based contrast agents used in contrast-enhanced spectral mammography (CESM) is unknown. If CESM, performed with lower dose of iodine based contrast agent, visualizes a tumor comparable to CESM with regular dose of contrast agent, patients can receive less contrast agent for CESM in future and thereby risking less side effects of the contrast agent. In order to study whether CESM remains unchanged at smaller amounts of contrast administration, a second CESM exam will be performed within one week of the first with a an alternative amount of contrast, it being either 80%, 60% or 40% of the original contrast dose. The settings of the CESM unit will remain unchanged.

Conditions
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Breast Neoplasm, Contrast-enhanced Spectral Mammography

Intervention / Treatment
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* Procedure: CESM with a reduced dose of contrast agent


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Female patient with histopathologically confirmed invasive breast cancer who recently underwent a clinical CESM exam without complications; Treated with primary surgery; Willing and able to undergo all study procedures; Has personally provided written informed consent. Age ≥ 18 Exclusion Criteria: Pregnancy Allergy for any of the ingredients of (Ultravist) contrast agent Being unable to give informed consent in person History of coronary arterial disease or unstable angina Acute or chronic severe renal insufficiency

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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Female

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
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: arm A (40%)<br>Patients randomized in arm A will receive a second CESM exam with 40% of the initial dose of the contrast agent. | Procedure: CESM with a reduced dose of contrast agent<br> <br> |
| Experimental: arm B (60%)<br>Patients randomized in arm A will receive a second CESM exam with 60% of the initial dose of the contrast agent. | Procedure: CESM with a reduced dose of contrast agent<br> <br> |
| Experimental: arm C (80%)<br>Patients randomized in arm A will receive a second CESM exam with 80% of the initial dose of the contrast agent. | Procedure: CESM with a reduced dose of contrast agent<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Accuracy of maximum tumor size measurements for breast cancer detected with the clinical CESM exam (reference) compared to the (experimental) CESM exams with varying (lower) dose concentrations. |  | After completion of final patient inclusion (e.g. 1 year) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Enhancement measurements for breast cancer detected with the clinical CESM exam (reference) compared to the (experimental) CESM exams with varying (lower) dose concentrations. |  | After completion of final patient inclusion (e.g. 1 year) |