title: Breast cancer metastasizing to the stomach mimicking primary gastric cancer: A case report.
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.
authors.affiliation: Kwangil Yim, Department of Hospital Pathology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul 06591, South Korea.
authors.forename: Kwangil
authors.initials: K
authors.lastname: Yim
authors.affiliation: Kwangil Yim, Department of Hospital Pathology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul 06591, South Korea.
authors.forename: Sang Mi
authors.initials: SM
authors.lastname: Ro
authors.affiliation: Kwangil Yim, Department of Hospital Pathology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul 06591, South Korea.
authors.forename: Jieun
authors.initials: J
authors.lastname: Lee
mesh_terms: D000368:Aged; D000970:Antineoplastic Agents / Q000627:therapeutic use; D001706:Biopsy; D001943:Breast Neoplasms / Q000175:diagnosis / Q000473:pathology*; D018279:Carcinoma, Signet Ring Cell / Q000175:diagnosis; D002352:Carrier Proteins / Q000737:chemistry; D003937:Diagnosis, Differential; D004358:Drug Therapy; D004415:Dyspepsia / Q000175:diagnosis; D004724:Endoscopy; D005260:Female; D041981:Gastrointestinal Tract / Q000473:pathology; D006023:Glycoproteins / Q000737:chemistry; D006801:Humans; D007150:Immunohistochemistry; D026901:Membrane Transport Proteins; D009362:Neoplasm Metastasis; D013274:Stomach Neoplasms / Q000175:diagnosis* / Q000556:secondary*; D014057:Tomography, X-Ray Computed
chemical_list: D000970:Antineoplastic Agents; D002352:Carrier Proteins; D006023:Glycoproteins; D026901:Membrane Transport Proteins; C488892:PIP protein, human
keywords: Breast cancer; GATA3; GCDFP-15; Gastric cancer; Immunohistochemical stain; Metastasis