Nipple inversion is an important finding on mammography and correlation with patient history is essential. When nipple abnormalities such as inversion are identified, it is important for the technologist to document them in the medical record / mammography worksheet so that the radiologist will be aware of the findings.
In most cases, nipple inversion results from a benign process that takes place gradually over a long period of time. It may be bilateral or unilateral. In cases of unilateral inversion that develops more rapidly (e.g. within a few months), the cause is more likely to be a malignancy, although a number of benign entities have also been associated with a rapidly developing nipple inversion, including:
- mammary duct ectasia
- postsurgical scarring
- fat necrosis
- fibrocystic change
- Mondor disease
Radiographic features
In cases where history is non-contributory or unavailable, or when inversion has developed rapidly, additional mammographic work-up is needed, including:
- spot compression views with the nipple in profile (to determine the presence of a retroareolar mass)
- craniocaudal and lateral spot magnification views to assess for microcalcifications
If the mammographic views are unrevealing, ultrasound should be performed.
