Primary gastric choriocarcinoma - a rare and aggressive tumor with multilineage differentiation: A case report

Table 1 The immunoprofile of gastric mucosa versus adenocarcinoma and choriocarcinoma component of a primary gastric tumor

	Antibody	Normal gastric mucosa	Adenocarcinoma component	Choriocarcinoma component
Markers for diagnosis	CK7	Positive	Positive	Positive
	CK20	Positive	Positive	Negative
	CK19	Negative	Negative	Negative
	CDX2	Positive	Positive	Negative
	HCG	Negative	Negative	Positive
	Inhibin	Negative	Negative	Positive - syncytiotrophoblast cells
	CEA	Negative	Positive	Negative
	Ki67 index	Internal control	100%	100%
	Synaptophysin	Internal control	Negative	Negative
	CD138	Positive-membrane	Positive-membrane+cytoplasm	Positive- syncytiotrophoblast cells
	Hep Par 1	Positive	Negative	Negative
	PLAP	Negative	Negative	Negative
	ALK	Negative	Negative	Negative
	AFP	Negative	Negative	Negative
	HER-2	Negative	Negative	Negative
	c-KIT	Negative	Negative	Negative
	P63	Negative	Negative	Negative
	CK5/6	Negative	Negative	Negative
	S100
Markers for microsatelite status	MLH-1	Positive	Positive	Positive
	MSH-2	Positive	Positive	Positive
	PMS-2	Positive	Positive	Positive
EMT markers	E-cadherin	Positive	Negative	Negative
	β-catenin	Positive-membrane	Positive-membrane	Positive-membrane
	Vimentin	Negative	Negative	Negative
	SLUG	Negative	Negative	Negative
Adhesion molecules	VSIG1	Positive-membrane	Negative	Negative
	CD44
Markers of angiogenesis	Maspin	Negative	Negative	Negative
	VEGF-A	Negative	Negative	Negative
	c-met	Positive	Positive	Positive

AFP: Alpha fetoprotein; ALK: Anaplastic lymphoma kinase; CEA: Carcinoembryonic antigen; CD: Cluster of differentiation; CK: Cytokeratin; EMT: Epithelial-mesenchymal transition; HCG: Human choriogonadotropin; Hep Par 1: Hepatocyte paraffin 1; PLAP: Placental alkaline phosphatase; VEGF: Vascular endothelial growth factor; VSIG: V-set and immunoglobulin domain containing 1.