Objective: The aim of this investigation was to explore the correlation between the levels of tumor-infiltrating CD8 + and CD4 + T cells and the quantitative pharmacokinetic parameters of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) in patients with advanced gastric cancer.
Methods: We retrospectively analyzed the data of 103 patients with histopathologically confirmed advanced gastric cancer (AGC). Three pharmacokinetic parameters, K ep, K trans, and V e, and their radiomics characteristics were obtained by Omni Kinetics software. Immunohistochemical staining was used to determine CD4 + and CD8 + TILs. Statistical analysis was subsequently performed to assess the correlation between radiomics characteristics and CD4 + and CD8 + TIL density.
Results: All patients included in this study were finally divided into either a CD8 + TILs low-density group ( n = 51) (CD8 + TILs < 138) or a high-density group ( n = 52) (CD8 + TILs ≥ 138), and a CD4 + TILs low-density group ( n = 51) (CD4 + TILs < 87) or a high-density group ( n = 52) (CD4 + TILs ≥ 87). ClusterShade and Skewness based on K ep and Skewness based on K trans both showed moderate negative correlation with CD8 + TIL levels ( r = 0.630–0.349, p < 0.001), with ClusterShade based on K ep having the highest negative correlation ( r = −0.630, p < 0.001). Inertia-based K ep showed a moderate positive correlation with the CD4 + TIL level ( r = 0.549, p < 0.001), and the Correlation based on K ep showed a moderate negative correlation with the CD4 + TIL level, which also had the highest correlation coefficient ( r = −0.616, p < 0.001). The diagnostic efficacy of the above features was assessed by ROC curves. For CD8 + TILs, ClusterShade of K ep had the highest mean area under the curve (AUC) (0.863). For CD4 + TILs, the Correlation of K ep had the highest mean AUC (0.856).
Conclusion: The radiomics features of DCE-MRI are associated with the expression of tumor-infiltrating CD8 + and CD4 + T cells in AGC, which have the potential to noninvasively evaluate the expression of CD8 + and CD4 + TILs in AGC patients.