Evaluation of the Effect of Fasting and Exercise on Uptake of Tc-99m Sestamibi in Breast Tissue

Study Overview
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Brief Summary
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The primary objective of this study is to determine if exercise, fasting, or eating prior to the molecular breast imaging study will have an effect on the uptake of the tracer in the breast tissue.

Detailed Description
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The primary objective of this study is to determine if exercise, fasting, or eating prior to a molecular breast imaging study will have an effect on the uptake of the radiotracer Tc-99m sestamibi in the breast tissue. Tc-99m sestamibi is primarily extracted by the liver. Changes in hepatic blood flow may therefore influence the amount of radiotracer available for uptake in the breast tissue.

Official Title
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Evaluation of the Effect of Fasting and Exercise on Uptake of Tc-99m Sestamibi in Breast Tissue

Conditions
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Molecular Imaging

Intervention / Treatment
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* Dietary Supplement: Meal
* Other: Exercise
* Radiation: Sestamibi
* Drug: Caffeine Tablet
* Other: External Heating


Participation Criteria
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Eligibility Criteria
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Inclusion criteria: Arm 1: 1. Able to fast overnight or for 6 hours 2. Non-diabetic 3. Age > 40 years 4. Negative pregnancy test, postmenopausal, or surgically sterilized 5. Negative mammogram at Mayo Clinic within the last 15 months (defined as screening mammogram or subsequent diagnostic workup with BI-RADS 1 or 2 final assessment) 6.No current breast concerns Arm 2: 1. Able to fast overnight or for 6 hours 2. Able to perform light to moderate exercise on an exercise bike 3. Non-diabetic and Body Mass Index < 25 4. Age > 40 years and < 70 years 5. Negative pregnancy test, postmenopausal, or surgically sterilized 6. Negative mammogram at Mayo Clinic within the last 15 months (defined as screening mammogram or subsequent diagnostic workup with BI-RADS 1 or 2 final assessment) 7. No current breast concerns 8. No history of coronary artery disease, angina, stroke or peripheral arterial disease. Arm 3: 1. Able to fast overnight or for 6 hours 2. Willing to consume a dose of caffeine (200 mg), equivalent to that of an 8 oz Starbuck brewed coffee. 3. Non-diabetic 4. Age > 40 years 5. Negative pregnancy test, postmenopausal, or surgically sterilized 6. Negative mammogram at Mayo Clinic within the last 15 months (defined as screening mammogram or subsequent diagnostic workup with BI-RADS 1 or 2 final assessment) 7. No current breast concerns Arm 4: 1. Able to fast overnight or for 6 hours 2. Non-diabetic 3. Age > 40 years 4. Negative pregnancy test, postmenopausal, or surgically sterilized 5. Negative mammogram at Mayo Clinic within the last 15 months (defined as screening mammogram or subsequent diagnostic workup with BI-RADS 1 or 2 final assessment) 6. No current breast concerns Exclusion Criteria: Pregnancy test (if necessary) is not negative, or the patient is unable to complete the pregnancy test Physically unable to sit upright and still remain still during two consecutive MBI studies over the course of a 2 hour period. Have undergone unilateral or bilateral mastectomy Breast implants or silicone injections Are unable to understand and sign the consent form Arm 2-also includes: Unable to perform light to moderate exercise for 12 minutes on a treadmill or a stationary bicycle Arm 3: Unwilling to consume a 200 mg dose of caffeine

Ages Eligible for Study
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Minimum Age: 40 Years
Maximum Age: 70 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Allocation: Non-Randomized
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Arm 4 - Fast vs Fast + External Heating<br>MBI will be performed in 52 subjects after an overnight fast with 4-6 mCi Tc-99m sestamibi. The subject will receive the usual Mayo gown for breast imaging. A skin temperature sensor will be taped to the anterior of one breast and skin temperature will be recorded. The subject will be asked to sit for 15 minutes in the waiting room prior to injection of the Tc-99m sestamibi. Just prior to injection, skin temperature will be recorded again. After completion of the first study the subject will then be given a warm towel robe and a small heating pad to be placed over the chest area. After 30 minutes, skin temperature will be recorded again immediately prior to injection of the second dose of Tc-99m sestamibi. The second MBI study will then be performed. | Radiation: Sestamibi<br>* reduce radiation dose<br>* Other names: Tc-99m;Other: External Heating<br>* Heating Pad and warm blanket robe<br>|
| Active Comparator: Arm 3 - Fasting vs. Fasting + Caffeine<br>MBI will be performed in 52 subjects after an overnight fast with 4-6 mCi Tc-99m sestamibi. The subject will then be instructed to consume 200 mg caffeine in tablet form. This is equivalent to the caffeine content of an 8 oz brewed coffee from Starbucks. After 45 minutes after consumption of the caffeine tablet, patients will receive a second injection of 4-6 mCi Tc-99m sestamibi and a repeat MBI study will be performed. | Radiation: Sestamibi<br>* reduce radiation dose<br>* Other names: Tc-99m;Drug: Caffeine Tablet<br>* effect of caffeine<br>* Other names: 200 mg Vivarin Tablet;|
| Active Comparator: Arm 2-Resting vs. Exercising<br>MBI will be performed in 25 subjects after an overnight fast with 4-6 mCi Tc-99m sestamibi. Patients will then be asked to perform moderate exercise on a treadmill for 6-10 minutes at a level of 70%-80% of maximum predicted heart rate. At  10 minutes, patients will receive a second injection of 4-6 mCi Tc-99m sestamibi and a repeat MBI study will be performed. | Other: Exercise<br>* effect of exercise<br>Radiation: Sestamibi<br>* reduce radiation dose<br>* Other names: Tc-99m;|
| Active Comparator: Arm 1-Fasting vs. Fed<br>MBI will be performed in 25 subjects after an overnight fast with 4-6 mCi Tc-99m sestamibi. Patients will then be instructed to consume 8-16 fluid oz of Ensure (350-700 calories). At 30 minutes after consumption of the meal, patients will receive a second injection of 4-6 mCi Tc-99m sestamibi and a repeat MBI study will be performed. | Dietary Supplement: Meal<br>* effect of meal<br>* Other names: Ensure;Radiation: Sestamibi<br>* reduce radiation dose<br>* Other names: Tc-99m;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Uptake of this radiopharmaceutical in breast tissue | Quantitative measurements of Tc-99m sestamibi uptake will be performed to measure the relative change in uptake between the two MBI scans. | 2 Days | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Normal subjects, Female, Molecular Breast Imaging, Fasting, Exercise, Tracer Uptake, Tc-99m Sestamibi, Prandial status, metabolic status, negative mammogram, Caffeine, External Warming