Use of Low-dose Molecular Breast Imaging for the Detection of Small Breast Lesions
Use of Low-dose Molecular Breast Imaging for the Detection of Small Breast Lesions
The purpose of this study is to show that improvements in the molecular breast imaging (MBI)
 technology will allow reduction of the administered dose of Tc-99m sestamibi while
 maintaining a sensitivity of 90% for tumor detection.
A total of 150 patients will be studied. Each patient will have a suspicious lesion on
 mammogram, ultrasound or breast magnetic resonance imaging (MRI) for which biopsy is
 scheduled. The lesion size on mammogram, ultrasound or breast MRI must be less than 2 cm in
 diameter and must be considered "suspicious" or "highly suspicious" for malignancy. Following
 injection of 8 mCi Tc-99m sestamibi, all patients will undergo craniocaudal (CC) and
 mediolateral oblique (MLO) views of each breast using a molecular breast imaging (MBI) system
 incorporating the latest hardware and software algorithms. Each image will be acquired for 10
 minutes in dynamic mode as 4 x 2.5 minute images. Summation of a given number of frames from
 each acquisition will yield images of an increasing mCi dose. Hence with an 8 mCi injection
 and a dynamic acquisition mode, we can evaluate the sensitivity of MBI as a function of
 administered doses of Tc-99m sestamibi ranging from 2 to 8 mCi. The thickness of the breast
 will be recorded to determine its relevance to lesion detectability.

 Patient Selection

 The goal of this study is to enroll 150 female patients in this study. The rationale for a
 study number of 150 patients is given in Appendix D. Patients referred for a mammogram,
 ultrasound or breast MRI study at Mayo Clinic Rochester will be considered for the study if
 they meet the following criteria:

 -  Have a lesion on mammogram, ultrasound or breast MRI that measured < 2 cm and is
 considered suspicious or highly suggestive of malignancy according to the Breast Imaging
 Reporting and Data System Atlas criteria (BI-RADS 4 or 5). (Note: while 2 cm is larger
 than the desired lesion size that we wish to study, this limit was recommended by our
 radiology colleagues as estimates of lesion size from mammography, ultrasound and MRI
 are not exact)

 -  Are scheduled for biopsy (needle and/or surgical biopsy) of the suspicious lesion

 -  Are > 18 years of age

 -  Had a negative pregnancy test or must be postmenopausal or surgically sterilized

 Eligible patients will be offered enrollment if the time interval between mammogram,
 ultrasound or MRI and scheduled biopsy allows for performance of MBI. Patients with prior
 needle biopsy of the lesion will be excluded from this study, as such biopsies may
 effectively remove all or part of the lesion. Prospective patients will be identified by the
 radiologist based on findings in their mammographic, ultrasound or MRI studies.
Inclusion Criteria:

 -

 Patients referred for a mammogram, ultrasound or breast MRI study at Mayo Clinic Rochester
 will be considered for the study if they meet the following criteria:

 -  Have a lesion on mammogram, ultrasound or breast MRI that measured < 2 cm and is
 considered suspicious or highly suggestive of malignancy according to the Breast
 Imaging Reporting and Data System Atlas criteria (BI-RADS 4 or 5). (Note: while 2 cm
 is larger than the desired lesion size that we wish to study, this limit was
 recommended by our radiology colleagues as estimates of lesion size from mammography,
 ultrasound and MRI are not exact)

 -  Are scheduled for biopsy (needle and/or surgical biopsy) of the suspicious lesion

 -  Are > 18 years of age

 -  Had a negative pregnancy test or must be postmenopausal or surgically sterilized

 Exclusion Criteria:

 -