The primary aim of this study is to show that the accuracy of Koning Breast CT-guided biopsy is at least equivalent to that of stereotactic-guided biopsy.

Inclusion Criteria:

• Female at least 35 years of age of any ethnicity
• Lesion seen on mammography
• Diagnostic report read as BI-RADS 4 or 5
• Will undergo biopsy no later than four weeks from date of mammogram
• Is able to undergo informed consent

Exclusion Criteria:

• Pregnancy

• Lactation

• Subjects with breast implants

• Subjects with physical limitations that may prohibit resting prone on the exam table, such as, but not limited to: frozen shoulder, recent heart surgery, pacemaker.

• Subjects who are unable to tolerate study constraints.

• Subjects 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 Hodgkins disease

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

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

  • Tuberculosis
  • Severe scoliosis