Usefulness of Cytological Scoring Method by Breast Fine Needle Aspiration Cytology on Breast Duct Dilatation and Cystic Lesions

AIM: The objective of this study was to apply a scoring method to fine needle aspiration cytology on breast duct dilatation and cystic lesions, to set an optimum cut-off value to differentiate between benign and malignant cases, and to identify features useful for cell judgment. MATERIALS AND METHODS: Samples were 23 preparations of specimens (12 benign and 11 malignant cases) suspected with intraductal lesions or cystic change by ultrasonography or mammography and cytology. The scoring system comprised the following 10 items, and each item was scored 1–3, with a total score of 10–30. Three items were concerning structural atypia: 1, scattered epithelial cells; 2, uneven irregular cluster edge; and 3, overlapping nuclei of epithelial cells, and seven items were concerning cellular atypia: 4, irregular nuclear size; 5, irregular nuclear morphology; 6, deep dyeing chromatin; 7, chromatin granularity; 8, chromatin distribution; 9, nucleolus; and 10, absence of myoepithelial cells. RESULTS: (1) Scoring cut-off value: malignancy is to be suspected when the score is 20.75 or higher (diagnostic accuracy: 95.7%). (2) Findings useful for cancer judgment: the sensitivity of the following four findings was high: uneven irregular cluster edge, irregular nuclear overlapping, chromatin granularity, and absence of myoepithelial cells. (3) Correlation among the findings: the findings correlated with malignancy were as follows: scattered epithelial cells versus uneven irregular cluster edge (rs = 0.8). CONCLUSION: Cytological evaluation by scoring lesions accompanied by intraductal dilatation and cystic change was a useful method capable of differentiating between benign and malignant cases at a high accuracy.