Contrast-enhanced CT parameters of gastric adenocarcinoma: Can radiomic features be surrogate biomarkers for HER2 over-expression status?

Abstract

Objective: The aim of this study was to determine the role of contrast-enhanced computed tomography (CE-CT) parameters in predicting the expression status of HER2 in gastric adenocarcinoma (GAC) patients before radical gastrectomy. Materials and Methods: A total of 460 GAC patients who underwent non-contrast CT (NC-CT) and CE-CT examinations before radical resection were enrolled in this retrospec-tive study. The radiologists reviewed their CT scans and recorded parameters, including CT attenuate value (CAV) and corrected CAV (cCAV). The pathologist identified the post-operative HER2 expression status, and HER2 expression status was evaluated by immuno-histochemical staining (IHC). The association between CE-CT parameters and HER2 expression status was analyzed. Results: Among the 460 patients, 84 patients had HER2 over-expression status, at a prevalence of 18.3%. The CAVs were significantly different between the 2 different HER2 expression groups in the non-contrast and arterial phases (non-contrast phase: p = 0.005; arterial phase: p < 0.001). Besides, there was a significant difference in the cCAVs between the 2 groups in the arterial phase (arterial phase: p = 0.003). Univariate and multivariate logistic regression analyses identified that the maximum diameter of tumor, differentiation degree, CAV in non-contrast, arterial, and portal phases, and cCAV in the arterial phase were predictive factors of HER2 expression status. Conclusion: Our analyses showed that the CE-CT parameters were significantly different between different HER2 expression groups. CE-CT parameters could serve as simple, objective predictive factors of HER2 expression status of GAC patients.