Relationship between CT characteristics and human epidermal growth factor receptor 2 expression in gastric cancers

Objective Retrospectively analyzing the CT features and human epidermal growth factor receptor 2 (HER2)-expression status of patients with pathologically proven gastric cancers to investigate the potential correlation between them. Materials and methods 433 patients with gastric cancers confirmed by pathology underwent CT scan. According to HER2-expression status, all patients were divided into two groups (HER2- negative [ n = 300] and positive [ n = 133]). CT features of primary gastric were reviewed and compared in both groups. CT findings were compared using Chi-square test, Fisher’s exact test, or the Student’s t test. Then binary logistic regression analysis was employed to identify the most significant differential CT features. Results Compared with HER2-negative gastric cancers, HER2-positive gastric cancers showed lower N stages (63.16% vs. 28.67%; p < 0.001), poorly defined margins (60.15% vs. 49.33%, p = 0.047), and hyperattenuation on portal phase (70.68% vs. 36.33%; p < 0.001). HER2-negative cancers (mean thickness, 1.72 cm) were slightly thicker than HER2-positive cancers (mean thickness, 1.51 cm), hepatic metastases and peritoneal seeding were slightly more frequently found in HER2-positive cancers (4.51% vs. 2%; 4.51% vs. 2.33%), but the difference was not statistically significant. By using binary regression analysis, hyperattenuation on portal phase (odds ratio [OR], 4.22; p < 0.001) and low risk of lymph node metastasis (OR, 0.25; p < 0.001) were significant independent factors that predict HER2-positive cancers. Conclusion Compared to HER2-negative cancers, HER2-positive gastric cancers show poorly defined margins, less-advanced N stage, and hyperattenuation on the portal phase.