Utility of Mid-treatment DWI in Selecting Pathological Responders to Neoadjuvant Chemoradiotherapy in Locally Advanced Esophageal Cancer

• Published in: Journal of gastrointestinal cancer 2023-06, Vol.54 (2), p.447-455
• Main Authors: John, Neenu Oliver, Irodi, Aparna, Thomas, Hannah Mary T., Abraham, Vijay, Sasidharan, Balu Krishna, John, Subhashini, Pavamani, Simon P.
• Format: Article
• Language: English
• Subjects: Cancer Research; Gastroenterology; Internal Medicine; Medicine; Medicine & Public Health; Oncology; Original Research; Radiotherapy
• ISSN: 1941-6628; 1941-6636
• DOI: 10.1007/s12029-022-00818-y

Purpose Pathological complete response correlates with better clinical outcomes in locally advanced esophageal cancer (LA-EC). However, there is lack of prognostic markers to identify patients in the current setting of neoadjuvant chemoradiotherapy (NACRT) followed by surgery. This study evaluates the utility of mid-treatment diffusion-weighted imaging (DWI) in identifying pathological responders of NACRT. Methods Twenty-four patients with LA-EC on NACRT were prospectively recruited and underwent three MRI (baseline, mid-treatment, end-of-RT) scans. DWI-derived apparent diffusion coefficient (ADC) mean and minimum were used as a surrogate to evaluate the treatment response, and its correlation to pathological response was assessed. Results Mid-treatment ADC mean was significantly higher among patients with pathological response compared to non-responders ( p  = 0.011). ADC difference (ΔADC) between baseline and mid-treatment correlated with tumor response ( p  = 0.007). ADC at other time points did not correlate to pathological response. Conclusion In this study, mid-treatment ADC values show potential to be a surrogate for tumor response in NACRT. However, larger trials are required to establish DW-MRI as a definite biomarker for tumor response.