Aspiration biopsy cytology of secretory carcinoma of the breast. A case report.

Secretory carcinoma diagnosed by aspiration biopsy cytology (ABC) disclosed many characteristic figures that were similar to a bunch of grapes, secondary mucous globular structures (MGSs) and clustered MGSs. The MGS was a unit structure of secretory carcinoma composed of a centrally located, small amount of mucus and two or more tumor cells covering it. Other findings were vacuolated cells and mucus in a clear background. The presence of the above findings, especially the "bunch of grapes" and related forms, were though to be essential findings in the cytologic differential diagnosis of secretory carcinoma by the ABC method. The origin of the characteristic features is discussed.