Criteria for the diagnosis of fibroepithelial lesions of the breast with liquid-based cytology.
OBJECTIVE
To establish diagnostic criteria for diagnosing and differentiating fibroepithelial lesions of the breast on ThinPrep (Cytyc Corp., Boxborough, Massachusetts, U.S.A.).


METHODS
Eighty-four fibroepithelial lesions were sampled by ultrasound-guided aspiration biopsy. Based on smears and histologic correlates, there were 55 fibroadenomas, 26 papillary neoplasms and 3 phyllodes tumors. The ThinPrep slides for each sample were reviewed retrospectively and evaluated for specific morphologic and cytologic features.


RESULTS
On ThinPrep slides, 95% of the fibroadenomas had a predominance of single myoepithelial nuclei, 89% had staghorn clusters, and 47% had myxoid stroma. Among the papillary neoplasms, 8% had a predominance of single columnar ductal cells, 31% had papillary groups, 23% had vessels, and 27% had collagenous spherulosis. The ThinPrep preparations of the phyllodes tumors showed that 67% had single myoepithelial nuclei, 33% had a predominance of single ductal cells, 67% had staghorn clusters, and 0% had myxoid stroma. A majority of the fibroadenomas and the papillary neoplasms showed mild to moderate ductal epithelial hyperplasia. A majority of the phyllodes tumors showed moderate ductal epithelial hyperplasia.


CONCLUSIONS
Fibroepithelial lesions of the breast can be accurately differentiated using ThinPrep samples based on the evaluation of specific cytologic and morphologic features, including the presence of staghorn clusters, fibromyxoid stroma, vessels, collagenous spherulosis, papillary clusters and predominance of myoepithelial nuclei or columnar cells in the background. However, the degree of ductal epithelial hyperplasia does not aid in the diagnosis.
Department of Pathology, New York Presbyterian Hospital-Weill Cornell Medical Center, New York, New York 10021, USA.
Asya S
AS
Ali
Diana
D
Yin
Davis
D
Yao
Madeline
M
Vazquez
D001707:Biopsy, Needle / Q000379:methods*; D001943:Breast Neoplasms / Q000175:diagnosis*; D002291:Carcinoma, Papillary / Q000175:diagnosis; D003937:Diagnosis, Differential; D005260:Female; D018226:Fibroadenoma / Q000175:diagnosis*; D006801:Humans; D003557:Phyllodes Tumor / Q000175:diagnosis; D012189:Retrospective Studies; D013048:Specimen Handling / Q000379:methods*