Inclusion Criteria:

- All women, age 40 or older, who are scheduled for biopsy after classification as
BI-RADS 4/5 and have had a screening or diagnostic full-field digital mammography
(FFDM) exam are eligible to participate, except for exclusions noted below.

- Able to provide informed consent.

Exclusion Criteria:

- Males

- Women less than 40 years old

- Pregnant women

- Lactating women

- Woman who have had bilateral mastectomies

- Women with physical limitations that may prohibit resting prone on the exam table,
such as, but not limited to: frozen shoulder, recent heart surgery, pace maker

- Women who are unable to tolerate study constraints, frail or unable to cooperate

- Women with large breasts that cannot be accommodated within the field of view of the
CT system

- Women who have received radiation treatments to the thorax for malignant and
nonmalignant conditions, such as (but not limited to)

- Treatment for enlarged thymus gland as an infant

- Irradiation for benign breast conditions, including breast inflammation after
giving birth

- Treatment for Hodgkin's disease

- Women who have participated in a prior breast clinical trial that gave additional
radiation dose, such as an additional mammogram.

- Women who have received large numbers of diagnostic x-ray examinations for monitoring
of disease such as (but not limited to)

- Tuberculosis

- Severe scoliosis