Emperipolesis in a common breast malignancy. A case report.
BACKGROUND
Emperipolesis is a phenomenon characterized by the presence of leukocytes/lymphocytes within the cytoplasm of other cells. The present report describes this unusual observation within epithelial cancer cells of the breast.


METHODS
A 52-year-old female presented with a hard, adherent lump over the right breast for one year. Fine needle aspiration and histopathologic examination of the tumor showed features of infiltrating duct carcinoma with emperipolesis as a striking feature of the tumor cells. The tumor showed a near-total response to neoadjuvant chemotherapy.


CONCLUSIONS
The mechanism and biologic significance of emperipolesis in producing a near-total response to neoadjuvant chemotherapy in the present case suggest its role in inducing a tumoricidal effect, possibly involving a cascade of chemokines.
D000951:Antigens, Neoplasm / Q000032:analysis / Q000276:immunology; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000008:administration & dosage; D001707:Biopsy, Needle; D001943:Breast Neoplasms / Q000737:chemistry / Q000188:drug therapy / Q000473:pathology*; D018270:Carcinoma, Ductal, Breast / Q000737:chemistry / Q000188:drug therapy / Q000473:pathology*; D017024:Chemotherapy, Adjuvant; D003520:Cyclophosphamide / Q000008:administration & dosage; D003593:Cytoplasm / Q000473:pathology; D004847:Epithelial Cells / Q000473:pathology; D005260:Female; D005355:Fibrosis; D005472:Fluorouracil / Q000008:administration & dosage; D006801:Humans; D006965:Hyperplasia / Q000473:pathology; D007150:Immunohistochemistry; D007633:Keratins / Q000032:analysis / Q000276:immunology; D007963:Leukocytes, Mononuclear / Q000473:pathology*; D008727:Methotrexate / Q000008:administration & dosage; D008875:Middle Aged; D014617:Vacuoles / Q000473:pathology
D000951:Antigens, Neoplasm; D007633:Keratins; D003520:Cyclophosphamide; D005472:Fluorouracil; D008727:Methotrexate