case_images: PMC5943893_01
case_images: Immunohistochemical study of the primary breast cancer by biopsy showing the tumor cells strongly positive for estrogen receptor (A) and progesterone receptor (B) (original magnification x400).
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case_images: PMC5943893_01_medi-97-e9550-g001.jpg
case_images: F1
case_images: Immunohistochemical analysis discovered that the tumor cells were positive for estrogen receptor (ER+) and progesterone receptor (PR++) (Fig. 1), and negative for human epidermal growth factor receptor 2 (HER2).
case_images: Endoscopic examination showing an ulcerative lesion in the duodenal bulb with no active bleeding.
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case_images: F2
case_images: Considering the patient's obvious obstructive symptoms of the upper gastrointestinal tract, we immediately ordered esophagogastroduodenoscopy, which showed gastric retention, mucosal congestion, and edema in the gastric antrum and duodenum (Fig. 2).
case_images: Immunohistochemical analysis showing the duodenal tumor cells positive for estrogen receptor (A), progesterone receptor (B), and GATA-binding protein 3 (C), but negative for caudal-related homeobox 2 (D) (original magnification x400).
case_images: medi-97-e9550-g003.jpg
case_images: PMC5943893_01_medi-97-e9550-g003.jpg
case_images: F3
case_images: Immunohistochemical analysis demonstrated the tumor was positive for ER, PR, and GATA-binding protein 3; other indicators, such as HER2, caudal-related homeobox 2, cytokeratin 7, and cytokeratin 20 were negative (Fig. 3).
case_images: Hematoxylin and eosin staining showing similar histological morphology in the primary breast cancer (A) and the metastatic duodenal adenocarcinoma (B) (original magnification x400).
case_images: medi-97-e9550-g004.jpg
case_images: PMC5943893_01_medi-97-e9550-g004.jpg
case_images: F4
case_images: Moreover, the results of hematoxylin eosin staining of the primary breast cancer and duodenal adenocarcinoma (Fig. 4) showed similar morphological features, which further confirmed the conclusion.