Juvenile papillomatosis of the breast

Juvenile papillomatosis (JP) of the breast is a relatively common benign localized proliferative lesion in the breast.

Epidemiology

As the name implies, it is mainly seen in young women (mean age ~19-23 years ^4,6) and is unusual in women over 30 years old.

Clinical presentation

Patients present with a firm, well-defined, mobile mass often in the periphery of the breast. There is usually no nipple discharge.

Pathology

Juvenile papillomatosis is a papillary proliferation of the ductal epithelium which partly fills up smaller ducts and distends them to a degree. Gross pathology often shows a well-circumscribed mass containing multiple small cysts (<2 cm) within a dense fibrous stroma (therefore sometimes termed Swiss cheese disease by pathologists). Lesions can vary in size, usually range from 1 to 8 cm.

Radiographic features

Breast ultrasound

They can appear as an ill-defined, inhomogeneous hypoechoic mass with multiple small (up to 4 mm) predominantly peripheral cysts. Microcalcifications may be seen at sonography ⁵.

Mammography

These lesions are usually negative on mammography ^4,5. Occasionally mammograms may show pleomorphic or amorphous microcalcifications, an asymmetric density or a prominent intraductal pattern.

Galactography

May show a multiple irregular filling defects within the breasts.

Breast MRI

Signal characteristics according to one report include ²:

• T1: hypointense lobulated mass
• T2: may show presence of multiple small internal cysts, best shown on this sequence and considered the most specific feature
• T1 C+ (Gd): may show marked rapid enhancement ¹¹
• dynamic sequence: shows a benign enhancement profile

Treatment and prognosis

Despite being a benign entity, it is considered by some to be a marker for familial breast cancer. Approximately 10% of those with papillomatosis are thought to develop breast cancer later in life ¹⁰.