Morphological CT signs of Epstein-Barr virus-associated locally advanced gastric cancer: a radiological-pathological...

To investigate the radiological phenotype of Epstein-Barr virus-associated locally advanced gastric cancer (EBVaGC) using computed tomography (CT) and to explore qualitative and quantitative CT signs for distinguishing it from EBV-negative gastric cancer (EBVnGC).

We enrolled 128 patients (64 with EBVaGC and 64 with EBVnGC). CT scans were analyzed for qualitative morphological indicators (tumor location, boundary sharpness, and the curled-edge sign [CES]) and quantitative indicators (tumor size and CT values). A radiological-pathological comparison was conducted to explore the pathological mechanisms underlying specific CT signs. Multivariate logistic regression was used to identify independent CT predictors of EBVaGC, and receiver operating characteristic (ROC) curve analysis was performed to assess diagnostic efficacy.

EBVaGCs were more likely to be located in the proximal part (p = 0.026), with a clearer boundary (p < 0.001), a smaller maximum length (p = 0.017), a higher thickness-to-length ratio (p = 0.006), and a lower unenhanced CT value (p = 0.011) than EBVnGCs. The CES was significantly more common in EBVaGC (39.1%) than in EBVnGC (12.5%) (p < 0.001), possibly due to lymphocyte-limited tumor infiltration. Binary logistic regression analysis revealed that tumor location, boundary sharpness, unenhanced CT value, and the CES were associated with EBVaGC (p < 0.05). A multivariate logistic regression model was constructed, with an AUC of 0.768.

EBVaGC exhibits specific morphological CT signs, among which the CES may reflect the mild growth pattern of the tumor margin.