Case Report
Copyright ©The Author(s) 2017. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Mar 28, 2017; 23(12): 2251-2257
Published online Mar 28, 2017. doi: 10.3748/wjg.v23.i12.2251
Breast cancer metastasizing to the stomach mimicking primary gastric cancer: A case report
Kwangil Yim, Sang Mi Ro, Jieun Lee
Kwangil Yim, Department of Hospital Pathology, Seoul St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul 06591, South Korea
Sang Mi Ro, Jieun Lee, Division of Medical Oncology, Department of Internal Medicine, Seoul St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul 06591, South Korea
Jieun Lee, Cancer Research Institute, the Catholic University of Korea, Seoul 06591, South Korea
Author contributions: Yim K reviewed the pathologic findings and wrote the manuscript; Ro SM accessed patient information and edited the manuscript; Lee J designed, reviewed and wrote the manuscript.
Institutional review board statement: This case report was approved by the Institutional Review Board at the Seoul St. Mary's Hospital (KC16ZISE0802).
Informed consent statement: Approved by the Institutional Review Board standards at the Seoul St. Mary's Hospital, the informed consent was omitted.
Conflict-of-interest statement: All authors have no personal, financial, or other conflicts of interest to declare.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Jieun Lee, MD, PhD, Division of Medical Oncology, Department of Internal Medicine, Seoul St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seocho-gu, Seoul 06591, South Korea. befamiliar@catholic.ac.kr
Telephone: +82-2-22586048
Received: November 24, 2016
Peer-review started: November 26, 2016
First decision: January 10, 2017
Revised: January 24, 2017
Accepted: March 2, 2017
Article in press: March 2, 2017
Published online: March 28, 2017
Abstract

Breast cancer with stomach metastasis rare with an incidence of 1% or less among metastatic breast cancer patients. We experienced a case of breast cancer metastasizing to the stomach in 65-year-old female patient. She experienced dyspepsia and poor oral intake before visiting the clinic. Diffuse infiltration with nodular mucosal thickening of the stomach wall was observed, suggesting advanced gastric cancer based on gross endoscopic finding. Spread of poorly cohesive tumor cells in the gastric mucosa observed upon hematoxylin and eosin stain resembled signet ring cell carcinoma, but diffuse positive staining for GATA3 in immunohistochemical stain allowed for a conclusive diagnosis of breast cancer metastasizing to the stomach. Based on the final diagnosis, systemic chemotherapy was administered instead of primary surgical resection. After 2 cycles of docetaxel administration, she showed a partial response based on abdominal computed tomography scan. This case is an unusual presentation of breast cancer metastasizing to the gastrointestinal tract.

Keywords: Gastric cancer, Breast cancer, Metastasis, Immunohistochemical stain, GATA3, GCDFP-15

Core tip: This case report describes a patient who was clinically diagnosed as advanced gastric cancer, but final pathological confirm diagnosis was to be breast cancer with gastric metastasis. Patient received systemic chemotherapy and is currently on partial response state at present.