10.6084/m9.figshare.4653838.v1 Park J.S. Park J.S. Rha S.Y. Rha S.Y. Chung H.C. Chung H.C. Jung M. Jung M. Kim K.H. Kim K.H. Jun H.J. Jun H.J. Kim H. Kim H. An J.Y. An J.Y. Kim H.-I. Kim H.-I. Cheong J.-H. Cheong J.-H. Hyung W.J. Hyung W.J. Noh S.H. Noh S.H. Kim H.S. Kim H.S. Supplementary Material for: Clinicopathological Features and Prognostic Significance of HER2 Expression in Gastric Cancer Karger Publishers 2017 Gastric cancer HER Predictive factor Chemotherapy 2017-02-15 14:52:46 Dataset https://karger.figshare.com/articles/dataset/Supplementary_Material_for_Clinicopathological_Features_and_Prognostic_Significance_of_HER2_Expression_in_Gastric_Cancer/4653838 <p><b><i>Background:</i></b> HER2 positivity is reported to be <20% in gastric cancer. Clinicopathological characteristics will be helpful to understand the biological features of HER2-positive gastric cancer. <b><i>Methods:</i></b> A total of 813 gastric cancer patients who underwent HER2 testing between January 2005 and December 2010 were included in this study. <b><i>Results:</i></b> Ninety-five (11.7%) patients had HER2-positive gastric cancer. Elevated serum carcinoembryonic antigen (CEA) concentration [odds ratio (OR), 5.629; p < 0.001] and differentiated histology (OR, 3.717; p = 0.002) were significant predictive factors for HER2 positivity in localized disease. For recurrent or metastatic disease, elevated serum CEA concentration (OR, 2.545; p < 0.001), differentiated histology (OR, 3.299; p < 0.001), pulmonary metastasis (OR, 3.321; p = 0.001), and distant lymph node metastasis (OR, 2.286; p = 0.002) were significant predictive factors. Median disease-free survival (DFS) was shorter in HER2-positive patients than in others, especially in stage I or II disease (24.7 vs. 49.2 months; p < 0.001). Among HER2-negative patients with stage II diseases, patients who received adjuvant chemotherapy had longer DFS than others (42.2 vs. 30.7 months; p = 0.025). <b><i>Conclusions:</i></b> Clinicopathological factors may be useful in predicting the HER2 positivity of gastric cancer. Further studies are needed to understand the molecular basis of HER2-positive gastric cancer. </p>