Immunotherapy and Targeted Therapy for Advanced Gastroesophageal Cancer: ASCO Guideline Update

The American Society of Clinical Oncology (ASCO) has published an updated clinical practice guideline on the use of immunotherapy and targeted therapy in advanced gastroesophageal cancer, appearing in the Journal of Clinical Oncology in April 2026. The update consolidates the latest evidence from pivotal trials to redefine recommended treatment sequences, biomarker-driven agent selection, and combination regimens for patients with unresectable or metastatic disease. Guideline updates of this scope directly influence day-to-day oncology practice worldwide, as they set the benchmark for standard-of-care decisions and inform insurance coverage and access policies. Clinicians treating upper gastrointestinal malignancies should review the revised recommendations, which span first-line and subsequent-line settings including checkpoint inhibitor combinations and HER2-directed therapies.