Collagenous Spherulosis Associated with Adenomyoepithelioma of the Breast

Abstract

Collagenous spherulosis (CS) associated with an adenomyoepithelioma (AME) of the breast is rare. This report describes a case of CS associated with an AME of the right breast, including the cytologic and histopathologic findings.A 51-year-old female presented with a slow-growing left breast mass that had been present for 5 months. A preoperative core needle biopsy showed the presence of layers or sheaths of myoepithelial cells around epithelial-lined spaces. Imprint cytology of the surgical material showed the presence of bundles of spindle cells with an admixture of epithelial cells. Spherical structures were also found. They were translucent or slightly light green with Papanicolaou staining and metachromatic with Giemsa staining. Grossly, the 1.5-cm lesion was solid and embedded within the breast parenchyma. Microscopically, it was composed of spindle or polygonal cells with eosinophilic cytoplasm and an epithelium lining spaces with many spherical structures. The spindle or polygonal cells were positive for myoepithelial markers and the epithelium was positive for epithelial markers by immunohistochemistry.There is no previous report describing the cytologic findings of CS associated with an AME of the breast. AMEs should therefore be considered an underlying pathology of CS of the breast.