Perioperative tislelizumab plus chemotherapy for locally advanced gastric cancer: A randomized, prospective phase 2 trial.

Perioperative tislelizumab plus chemotherapy significantly improves pathological response in tsMHC-II-positive gastric cancer patients, with a 61.8% mPR rate versus 26.5% for chemotherapy alone.

• Why it matters: Reliable biomarkers are needed to identify gastric cancer patients who will benefit most from immunotherapy, addressing a critical gap in personalized treatment strategies.
• What they did: A randomized phase 2 trial enrolled 136 patients with operable gastric or gastroesophageal junction cancer, stratified by tsMHC-II expression, and compared perioperative tislelizumab plus chemotherapy to chemotherapy alone.
• The result: tsMHC-II positivity predicts a substantial benefit from immunotherapy, enabling more targeted treatment approaches and supporting further validation of tsMHC-II as a predictive biomarker.