To review the synergistic mechanisms, clinical research directions, and future challenges of combining preoperative radiotherapy and immunotherapy in treating locally advanced gastric cancer and gastroesophageal junction adenocarcinoma.
Approach:
Biomarker Validation: Current evidence on predictive biomarkers for patient stratification remains inconclusive, necessitating further validation.
Key Findings:
Neoadjuvant chemoradiotherapy combined with ICIs yields a pathological complete response rate of 22.6% to 38.2%.
Predictive biomarkers like PD-L1 expression and tumor mutational burden require further validation.
Optimal integration of RT and immunotherapy remains controversial, with various factors influencing efficacy and adverse events.
Large-scale RCTs are needed to confirm survival benefits and establish standardized protocols.
Interpretation:
The integration of RT and immunotherapy represents a promising strategy for treating locally advanced gastric cancer, but further research is essential to validate biomarkers and optimize treatment protocols.
Limitations:
Conflicting results from phase I-II trials highlight the need for robust patient stratification.
Current evidence on biomarkers for identifying responders is inconclusive.
Lack of long-term survival outcomes in recent trials.
Conclusion:
Future efforts should prioritize the validation of predictive biomarkers and the conduct of large-scale trials to establish effective treatment protocols.
Harold Burstein, MD, PhD, and Erica Mayer, MD, MPH discuss results from the TRAK-ER trial, which were presented at the 2026 ESMO Breast Cancer Congress.
