Fine-needle aspiration cytology of cystic hypersecretory ductal carcinoma in situ of the breast: a case report.

Cystic hypersecretory intraductal carcinoma is an unusual, cystic form of intraductal breast carcinoma affecting middle-aged women. Cytopathologists have rarely encountered this lesion, with only 2 other cases having been previously reported (Colandrea et al., Arch Pathol Lab Med 1988:112:560-563; Kim et al., Acta Cytol 1997;41:892-896). In our cases, the cytologic findings of both air-dried, Diff-Quick-stained and ethanol-fixed, Papanicolaou-stained smears are presented. The cytologic hallmarks of this entity include the presence of a few scattered epithelial cells with bland nuclear morphology in a background of extensive, amorphous, pink-staining material. Cytomorphologically, the differential diagnosis includes other entities containing pink-staining material such as colloid carcinoma, mucocele-like lesion of the breast, and benign fibrocystic change.