Secretory carcinoma of the breast. Correlation of aspiration cytology and histology.

We analyzed the fine needle aspiration findings in five cases of secretory carcinoma of the breast in adults to clarify their cytomorphologic features and correlate them with their histology. The cytologic smears revealed grapelike clusters of mucous globular structures (MGSs); single MGSs; clusters and sheets of cells with pale green and slightly granular cytoplasm with or without intracytoplasmic vacuolization; some ordinary duct carcinoma-like arrangements; scattered, single, vacuolated cells; some extracellular mucus; and a clean background. The MGSs were globular structures consisting of distinctive vacuolated cells containing large globules of a secretory product. The cytologic findings showed a similar wide variation in the range of histologic appearances; however, the grapelike clusters of MGSs, which corresponded to a microcystic or microfollicular pattern histologically, were present in most cases and should suggest a diagnosis of secretory carcinoma.