Third-Line Treatment for Advanced Gastric Cancer with HER2 Overexpression
Clinical Scenario
This protocol addresses advanced or metastatic gastric cancer in patients whose tumours demonstrate HER2 overexpression — specifically HER2 IHC 3+, or HER2 IHC 2+ confirmed by FISH positivity — who have progressed after two prior lines of systemic therapy.
HER2 Overexpression in Gastric Cancer
HER2 status is a critical biomarker in advanced and metastatic gastric cancer. Overexpression, confirmed by IHC 3+ or IHC 2+ with FISH-positive testing, defines a distinct patient subgroup that drives treatment selection across lines of therapy.
Third-Line Treatment Approach
For patients with HER2-overexpressing advanced gastric cancer who have progressed on two prior lines of therapy, a specific oral combination agent is recommended for third-line treatment. Additional treatment alternatives are detailed in the full protocol.
References
DOI: 10.1016/j.annonc.2022.07.004
- Adding trastuzumab to ChT is recommended for patients with HER2-overexpressing (HER2 IHC 3+ or IHC 2+/FISH positive) gastric cancer, based on the phase III ToGA study.
- For patients previously treated with two lines of therapy, trifluridine-tipiracil is recommended [I, A; ESMO-MCBS v1.1 score: 3]. Alternative treatments include a taxane or irinotecan [II, B].