Investigation of Diagnostic Improvement Gained Through Optimization of MR Methods for Breast Cancer Detection

MR examinations will be performed on a 3.0 Tesla GE whole-body scanner using an elliptically
driven body coil for transmit and a multi-channel bilateral breast coil for receive. The
multi-channel coil will consist of 8, 16 or 31 channels. DCE-MRI: DCE-MRI will be carried out
using a three-dimensional (3D) turbo fast lowangle gradient echo sequence (TFE) combined with
parallel acquisition Sensitivity Encoding (SENSE) technique. The imaging plane will be set in
axial plane so that both breasts are included in the images. One image will be acquired
before and four images will be acquired after intravenous administration of a standard dose
of 0.1 mmol per kg of body weight of Gadavist (Schering AG, Germany) at a rate of 3ml/sec.
with subjects in the prone position, breathing normally during the scan. The total scan time
for the DCEMRI will be about 8 minutes.

Pharmacokinetic parameters, including the volume transfer constant Ktrans, the fractional
volume of extravascular extracellular space of the target tissue ve, and the rate constant
kep, will be estimated by fitting a pharmacokinetic model to the time-intensity curves
obtained from the DCE-MRI. In this study, the concentration of tracer Ct(t) after bolus
injection is assumed to obey the model proposed by Tofts and Kermode (20). DWI-MRI
examinations: The DWI acquisition will occur before and/or after contrast enhancement used in
DCE imaging. Immediately after the completion of imaging with the 16 (or 31) channel breast
coil, the patient will be repositioned replacing the breast coil with an 8 channel breast
coil and additional DWI acquisitions will be made. Data for apparent diffusion coefficient
assessment on diffusion-weighted imaging will be acquired using a single-shot Echo Planar
Imaging sequence in the transverse plane. The DWI protocol will acquire images with up to 16
different b values. Slice dependent shimming will be performed to provide the maximum B0
homogeneity for each slice. The total scan time for the DWI-MRI will be about 5 minutes.

All of the DWI image data from the MRI examinations will be stored on a dedicated HIPPA
compliant computer workstation (located in room NE6.114) for analysis. The relevant
parameters will be mean ADC and the histogram of ADC in the lesions.

Conductivity imaging: A B1 map and a spin echo image will be acquired for measuring tissue
conductivity (21).

The images used for conductivity measurement will be anonymized and sent to the manufacturer
for further development of post-processing techniques.

Inclusion Criteria:

Women with Breast Imaging-Reporting and Data System (BI-RADS) 4 or 5 Age ≥ 18 years Ability
to understand and the willingness to sign a written informed consent.

Exclusion Criteria:

Subjects who have had a needle biopsy of the suspicious area within the last 6 weeks
Subjects who have contraindication to contrast enhanced MRI examination.

Contraindications to MRI examinations include:

Medically unstable

- Heart failure

- Unstable angina

- Child bearing

- Lactating Any contraindication per MRI Screening Form (Appendix A attached).

- Implants contraindicated at 3T, pacemakers

- Poorly controlled diabetes

- Body weight greater than 300 pounds

- Claustrophobic Since each patient is receiving a gadolinium based contrast agent
intravenously:

- eGFR < 60 mL/min/1.73m2

- Sickle cell disease

- Hemolytic anemia

Subjects must not be pregnant or nursing due to the potential for gadolinium contrast
agents to harm fetuses or nursing infants.