Histology of Functional Density in Postmenopausal Breast

Study Overview
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Brief Summary
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Increased mammographic density is recognized as an important risk factor for developing breast cancer, however, the underlying mechanism explaining this relationship is unclear. The investigators hypothesize that Molecular Breast Imaging (MBI) can more accurately distinguish dense tissue on mammography which is at high risk from dense tissue at low risk by indicating cellular activity in dense tissue as radiotracer uptake (functional density) in the breast. In this pilot study, the investigators want to compare the histological characteristics of breast tissue in patients with who have similar density on mammography but different levels of functional density on MBI.

Official Title
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Pilot Study to Examine Histological Characteristics of Mammographic Density With Molecular Breast Imaging: Part 1 - Postmenopausal Women

Conditions
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Dense Breasts, Breast Cancer

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 40 or older Be postmenopausal as defined as having at least 12 consecutive months of amenorrhea Screening mammogram performed at Mayo Clinic Rochester within one year prior to the current MBI study which demonstrates Negative or benign assessment (BIRADs category 1-2) No proliferative benign lesions (e.g. fibroadenomas) identified Heterogeneously dense or extremely dense parenchyma (BIRADs density category 3 or 4) MBI performed less than one month prior to biopsy demonstrating either significant FD or photopenic FD. Exclusion criteria: Using any exogenous hormones (e.g., hormonal contraceptives, sex steroid hormones) or any estrogen receptor modulating drugs (e.g., tamoxifen, raloxifene) or any aromatase inhibitors within six months prior to study biopsy. Personal history of any cancer, except non-melanomatous skin cancer Current breast symptoms Breast implants Known allergy to local anesthetic. History of bleeding complications from prior interventions Current use of anticoagulants (e.g., Coumadin or other blood thinners) Major medical condition

Ages Eligible for Study
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Minimum Age: 40 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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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| proportion of epithelium vs stroma |  | within 1 month of functional density assessment on MBI | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Degree of lobular involution | Degree of lobular involution as assessed through qualitative and quantitative measurements will be compared between dense tissue which appears photopenic on MBI and dense tissue which appears functionally active on MBI. | within 1 month of functional density assessment on MBI | 
| Ki-67 cellular proliferation index | Degree of cellular proliferation as assessed through Ki-67 index will be compared between dense tissue which appears photopenic on MBI and dense tissue which appears functionally active on MBI. | within 1 month of functional density assessment on MBI |