Solitary intraductal papillomata occur most often in women from 50 to 60 years of age. Patients often do not have a palpable mass, but rather present with a serous or bloody nipple discharge.
Aspiration of a papilloma shows tight clusters and three-dimensional groups of epithelial cells, possibly in a papillary arrangement, which is more obvious in cell block preparations. Individually scattered columnar-shaped cells and spindle-shaped stromal cells can occasionally be present.
Surgical excision is always advised for the differential diagnosis with well-differentiated papillary carcinoma. Fibroadenoma is also included in the differential diagnosis, when smears from papillomata show a branching epithelial pattern.