Secondary Logo

Journal Logo

Institutional members access full text with Ovid®

“Extramammary-Type” Paget Disease of the Breast

Fernandez-Flores, Angel, MD, PhD*,†,‡; Eraña, Itziar, MD§; Cuevas, Jesus, MD, PhD§

The American Journal of Dermatopathology: October 2018 - Volume 40 - Issue 10 - p 711–720
doi: 10.1097/DAD.0000000000001105
CME Article

Background: Mammary Paget disease and extramammary Paget disease (EMPD) have different prognoses. Because they are indistinguishable on histopathological grounds, they must be distinguished on a topographical basis.

Objective: To study cases of Paget disease of the breast, which show similarities to EMPD.

Methods: Cases were selected by 2 different approaches: (1) those with an exceptionally good evolution and no evidence of subjacent tumor and (2) those expressing MUC5AC.

Results: Five cases were collected. All cases showed an indolent behavior with a known long clinical history in 2 cases (9 and 25 years, respectively) and a long follow-up in all cases but one (4–8 years). In all cases but one, surgery was performed, and no parenchymal tumor was found (either intraductal or infiltrating). All cases expressed cytokeratin 7 and MUC5AC without expression of MUC2, S100, or p40.

Limitations: The short number of cases is a limitation of this study. In addition, case 5 is recent, so we have a very short follow-up.

Conclusions: Some cases of mammary Paget disease behave like EMPD with slow progression and with no underlying associated tumor. Immunoexpression of MUC5AC might be a clue to identify them.

*Consultant Histopathologist, Department of Cellular Pathology, Hospital El Bierzo, Ponferrada, Spain;

Consultant Histopathologist, Department of Cellular Pathology, Hospital de la Reina, Ponferrada, Spain;

Associate Researcher, CellCOM-SB Group Department, Institute for Biomedical Research of A Coruña (INIBIC), University of A Coruña (UDC), A Coruña, Spain; and

§Consultant Histopathologist, Department of Anatomic Pathology, Hospital Universitario de Guadalajara, Guadalajara, Spain.

Correspondence: Angel Fernandez-Flores, MD, PhD, Servicio de Anatomía Patologica, Hospital El Bierzo, Medicos sin Fronteras 7, 24411 Ponferrada, Spain (e-mail:

All authors, faculty, and staff in a position to control the content of this CME activity and their spouses/life partners (if any) have disclosed that they have no financial relationships with, or financial interests in, any commercial organizations pertaining to this educational activity.

IRB status: IRB was not required.

Copyright © 2018 Wolters Kluwer Health, Inc. All rights reserved.