Key clinical point: Firstline trastuzumab-based chemotherapy shows poorer survival in patients with rescued vs initially human epidermal growth factor receptor 2 (HER2)-positive advanced gastric cancer.
Major finding: The median follow-up duration was 47.6 months. Rescued HER2-positive patients had a higher rate of immunohistochemistry (IHC) score 2+/in situ hybridization-positive (ISH+; 37.0%) tumors. The median progression-free survival (PFS; 5.7 vs 8.4 months; P = .034) and overall survival (OS; 11.3 vs 16.7 months; P = .02) were significantly shorter in IHC 2+/ISH+ vs IHC 3+ patients. Rescued vs initially HER2-positive patients had worse PFS (5.4 vs 7.8 months; P = .017) and OS (10.4 vs 16.3 months; P = .036).
Study details: A retrospective analysis of 153 patients with HER2-positive advanced gastric cancer who received first-line trastuzumab-based chemotherapy.
Disclosures: No funding source was identified for this work. The authors received consulting fees and honoraria. JH Cheon was the founder and shareholder of Novomics.
Source: Bang K et al. Association between HER2 heterogeneity and clinical outcomes of HER2-positive gastric cancer patients treated with trastuzumab. Gastric Cancer. 2022 (May 7). Doi: 10.1007/s10120-022-01298-6