Case 12 continued

The breasts are heterogeneously dense, which may lower the sensitivity of mammography. A sentence about the overall breast density should appear in the body of each report. This conveys some sense of the sensitivity of mammography to detect cancer in the individual patient. Overall the sensitivity decreases with increasing breast density.

This is the patient's mammogram 1 year prior:
 

What is the most likely explanation for the changes?

• Menopause
• Pregnancy
• Hormone Replacement Therapy
• Estrogen-producing tumor
• Mastitis