Correlation between Histogram Analysis Parameters Derived from DCE-MRI and the Expression of PD-L1 in Esophageal Squamous Cell Carcinoma. A Preliminary Study

Purpose: To investigate the correlation between the histogram parameters (Ktrans, Kep, Ve) of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and programmed death-ligand 1 (PD-L1) expression in esophageal squamous cell carcinoma (ESCC).Methods: Overall, 23 ESCC patients without prior surgery underwent DCE-MRI before treatment.Histogram parameters of DCE-MRI were extracted, and PD-L1 expression in lesions was detected by immunohistochemistry. PD-L1 expression was evaluated using three scoring methods: Tumor Proportion Score (TPS), Combined Positive Score (CPS), and Immune Cell Score (ICS).Results: CPS correlated with the kurtosis and skewness coefficients derived from the Ktrans (r = -0.416,p = 0.048 and r = -0.507,p = 0.013).Additionally, CPS correlated with the P90 and kurtosis coefficients derived from the Kep (r = 0.424, p = 0.044 and r = 0.422, p = 0.044).ICS correlated with the mean value derived from the Ktrans (r = 0.431, p = 0.040).No association was observed between DCE-MRI parameters and TPS.Conclusion: Ktrans and Kep related histogram analysis parameters derived from DCE-MRI showed correlation with PD-L1 expression in immune cells of ESCC.Therefore, histogram analysis parameters derived from DCE-MRI may serve as an effective imaging biomarker for pre-therapeutic assessment of immunotherapy eligibility in patients with ESCC.