BREAST CYTOPATHOLOGY

Ductal/Nipple Adenoma 73
Breast Lesions Diagnosed as “Papillary”
on Fine-Needle Aspiration
True papillary lesions of the breast comprise a diverse
group of benign and malignant entities. A number of
studies have shown that most of these turn out to be “nonpapillary”
on histologic resection (particularly the malignant
cases). This, therefore, raises the question, Do we tend
to overinterpret “papillary architecture” on FNA? Papillary
lesions were considered an “indeterminate” category at the
National Cancer Institute–sponsored consensus conference
in 1996.
• Benign follow-up (in two thirds of cases)
Intraductal papilloma
Papillomatosis
Fibroadenoma
Fibrocystic changes (with papillary hyperplasia)
• Malignant follow-up (one third of cases)
Ductal carcinoma (both in situ and invasive)
Phyllodes tumor
Ductal/Nipple Adenoma
Also known as papillary adenoma, ductal/nipple adenoma
is a benign mass lesion of the nipple with a prominent
papillary architecture. Most adenomas present with nipple
discharge.
Clinical Features
• This uncommon neoplasm presents as a discrete, sharply
circumscribed nodule with a sclerotic stroma. Most ductal
adenomas are up to 2 cm in size and are either solitary or
multiple but rarely bilateral.