Method: HER2 was assessed by both IHC (Pathway 4B5™) and FISH (PathVysion™) in 164 GC samples. Reactions were evaluated according to guidelines. HER2 was considered positive in case of strong protein expression (3+) and/or gene amplification (ratio ≥2.0). Frequencies of IHC and FISH scores, incidence of HER2+ GC and concordance (chi-square) of applied methods were analysed. Results: IHC score distribution: neg (0) Objective: Gastric glomus tumors are rare neoplasms originated from modified smooth muscle cells of the glomus bodies. Such lesions present a diagnostic challenge in biopsy material. Herein, we report a case of gastric glomus tumor in a 35-year-old woman. Method: A 35-year-old woman presented with refractory epigastralgy. A gastrointestinal stromal tumor of the gastric antrum was suspected. The diagnosis was made after ultrasound-guided endoscopic biopsy, followed by an endoscopic submucosal resection. Results: The biopsy showed tight convolutes of capillarysized vessels surrounded by collars of small, rounded cells set in a hyalinized, myxoid stroma. Immunohistochemically, these cells were positive for smooth muscle actin and type IV collagen (pericellular pattern), synaptophysin (focal positivity) and negative for CD34, CD117, desmin, S100 and cytokeratins. The diagnosis of gastric glomus tumor was rendered. The resection specimen revealed a submucosal well-circumscribed 2×1,5×1,5 cm nodule with identical histological features. The patient was disease-free 12 months postoperatively.