Fig. 4. Baseline genomic landscape in the enrolled patients with HER2-positive gastric cancer treated with the first-line quadruplet regimen.

a Baseline (pretreatment) tumor tissue-targeted DNA sequencing results grouped by the best response and related clinicopathologic features (n = 31). Curated pathways and selected genes altered in 6% or more of the patients are shown. Other pathways included those related to the cell cycle and the Hippo, MYC, and NRF2 pathways. Vertical dashed lines indicate groups by the best response. b–d Kaplan–Meier survival curves with PFS stratified by pretreatment ERBB2 amplification as determined via NGS (b n = 35), RTK-RAS pathway gene alterations (c n = 31), and HLA-B-corrected neoantigen load (d n = 31). In (b–d), two-sided P-values for survival associations were calculated using the log-rank tests. Hazard ratios and corresponding 95% CIs were estimated using Cox proportional hazard regression model. No adjustments for multiple comparisons were made. Crosses denote censored observation, and the number at risk is indicated below the plots. HER2, human epidermal receptor 2; ERBB2, Erb-B2 receptor tyrosine kinase 2; HLA, human leukocyte antigen; NGS, next-generation sequencing; PFS, progression-free survival; RTK, receptor tyrosine kinase.