Gastric schwannoma: Computed tomography and perigastric lymph node characteristics

Figure 1 Gastric schwannoma in the lesser curvature of the gastric body in a 52-year-old woman. A: Plain axial computed tomography (CT) scan shows an oval, well-defined, exophytic, and homogeneous mass, with a density of 27 Hounsfield units (HU) lower than that of the erector spinae (54 HU); B-D: Axial contrast-enhanced CT scans in the arterial, portal venous, and delayed phases show progressive homogeneous enhancement. The CT values in the three phases are 53, 66, and 70 HU, respectively. The arterial phase shows enhanced mucosal clarity, suggesting a submucosal mass. Localized mucosal disruption indicates a shallow ulcer (thin arrow). Additionally, homogeneously enhanced perigastric lymph nodes (thick arrow) are detected adjacent to the mass.

Figure 2 Gastric schwannoma in a 56-year-old woman presenting with epigastric discomfort and black stool. A: Arterial phase-enhanced computed tomography (CT) shows an endoluminal tumor with deep ulceration (arrow); B: Gross examination revealed that the tumor’s cut surface was yellowish, with an ulcer as observed in the CT image; C: Tumor is primarily composed of spindle-shaped cells with a characteristic peripheral lymphoid cuff (hematoxylin and eosin stain; original magnification, × 100); D: The tumor is strongly positive for S-100 protein.

Figure 3 Computed tomography values of all 23 cases in each phase of the contrast-enhanced scan. CT: Computed tomography; HU: Hounsfield units; PS: Plain phase; AP: Arterial phase; PP: Portal phase; DP: Delayed phase.