Single-center retrospective study of prognostic significane of low HER2 expression in gastric cancer

A retrospective study at Iwai Hospital (Iwate prefecture, Japan) evaluated the prognostic significance of low HER2 expression in gastric cancer. Among 129 patients treated for HER2-non-amplified gastric cancer from 2013 to 2019, low HER2 expression was found in 33 patients (26%). Clinicopathological characteristics were not significantly different between the HER2-low and the HER2-null groups. The overall survival was signficantly longer in the HER2-low group, driven by the overall survival difference among stage III patients and among patients receiving adjuvant chemotherapy. In multivariate analysis, HER2-null status was associated with worse survival (HR 3.01; p=0.02). The authors conclude that these results highlight the prognostic relevance of low HER2 expression in gastric cancer.