The fine-needle aspirates of two cases of noninfiltrating papillary carcinoma (PC) and three examples of early invasive PC of the breast were examined. In three cases in which the tumors displayed cuboidal or polygonal cells the aspirates showed papillalike clusters of tumor cells with relatively “strong” cellular cohesiveness. Single and small aggregates of tumor cells as well as hemosiderin-laden or foamy macrophages were also present. Aspirates from the two PCs predominantly consisting of tall columnar epithelial cells revealed only monolayered and multilayered epithelial fragments with folding in one case. In the other case large epithelial fragments and small tight clusters of polygonal tumor cells were present. No bipolar nuclei of myoepithelial cells were identified in all cases. No specific cellular features permitting the differentiation between noninfiltrating and early invasive breast PCs were identified in this small series. Staining for carcinoembryonic antigen using the peroxidase-antiperoxidase technique was performed on aspiration smears of three cases. It revealed a positive cytoplasmic reaction in two cases. © 1992 Wiley-Liss, Inc.