Apparent Diffusion Coefficient Values Measured by Diffusion-Weighted Imaging Predict Chemoradiotherapeutic Effect for Advanced Esophageal Cancer

Background: The purpose of this study was to assess whether apparent diffusion coefficient (ADC) values of esophageal squamous cell carcinoma (ESCC) predict responses to chemoradiotherapy (CRT) and/or patient prognosis. Methods: Magnetic resonance images were acquired to construct the diffusion-weighted images, and the ADC values were calculated before CRT in 80 patients with ESCC. A high-ADC group responded better to CRT than did a low-ADC group (p < 0.01). We divided the 80 patients into two groups based on the operating characteristic analysis: one group comprised patients with ADC values higher than the average ADC of the esophageal cancer tissue (1.10 × 10–3 mm2/s), and the other group comprised those whose ADC values were less than the average value. A Kaplan-Meier analysis showed that the survival rate in the high-ADC group was significantly better than that in the low-ADC group (p = 0.04). Conclusion: Our results indicate that the ADC value may be a useful marker to predict treatment response as well as survival for patients with ESCC.