PMC4749200_01
Abdominopelvic CT scan revealed 16 mm enhancing mass lateral to right psoas major muscle which could be metastatic mass
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F1
A CT scan of the chest, abdomen, and pelvis with oral and intravenous contrast were performed; chest CT scan showed an 11*5 millimeters lung nodule in right middle lobe, abdominal and pelvic CT scan revealed a small mass lateral to right psoas muscle (Fig. 1).
The H&E (10X & 40 X microscopic powers) slides showed infiltrative atypical nests with vague gland-like features
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F2
A CT-guided core needle biopsy of the lung nodule and right psoas muscle was done that results were negative for malignancy in lung specimen but the histological and immunohistochemical findings of psoas muscle supported a diagnosis of adenocarcinoma consistent with primary adenocarcinoma of the GEJ (Fig. 2). 
The infiltrative nests revealed positive reaction with CK7, MUC5AC, and Her2, as well as negative reaction with CK20, CDX2 and TTF1
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F3
The neoplastic cells were negative CK20, CDX2 and TTF1 (Fig. 3).