title: Metastatic mammary carcinomas with endocrine features: potential diagnostic pitfalls.
abstract: Mammary carcinomas with endocrine differentiation (MCED) are an uncommon subtype of breast carcinomas that are morphologically indistinguishable from low-grade endocrine neoplasms arising in other organs. Aspirates of MCED yield relatively monotonous cells with eccentrically placed nuclei containing characteristic "salt and pepper" chromatin. In the breast, these features represent MCED. In extramammary sites, the differential is more extensive, and diagnosing MCED metastases to the lung, a common location for primary and metastatic endocrine tumors, can be a challenging task, with significant clinical implications. Although primary MCED have been described extensively in the cytology literature, secondary pulmonary MCED have not been reported to the best of our knowledge. We report three cases of MCED metastatic to the lung and present the cytological and immunohistochemical features.
authors.affiliation: Department of Pathology, New York Presbyterian Hospital, Columbia University Medical Center, New York, New York 10032, USA. aas177@columbia.edu
authors.forename: Anjali
authors.initials: A
authors.lastname: Saqi
authors.forename: Martin W
authors.initials: MW
authors.lastname: Oster
authors.forename: Madeline F
authors.initials: MF
authors.lastname: Vazquez
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D044963:Biopsy, Fine-Needle; D001940:Breast / Q000737:chemistry / Q000473:pathology; D001943:Breast Neoplasms / Q000378:metabolism / Q000473:pathology*; D002352:Carrier Proteins / Q000032:analysis; D002864:Chromogranins / Q000032:analysis; D003937:Diagnosis, Differential; D004702:Endocrine Glands / Q000473:pathology*; D005260:Female; D006023:Glycoproteins / Q000032:analysis; D006801:Humans; D007150:Immunohistochemistry; D008175:Lung Neoplasms / Q000378:metabolism / Q000556:secondary*; D026901:Membrane Transport Proteins; D008875:Middle Aged; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000032:analysis; D011960:Receptors, Estrogen / Q000032:analysis; D011980:Receptors, Progesterone / Q000032:analysis; D016708:Synaptophysin / Q000032:analysis
chemical_list: D002352:Carrier Proteins; D002864:Chromogranins; D006023:Glycoproteins; D026901:Membrane Transport Proteins; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; D016708:Synaptophysin; C488892:PIP protein, human