Metastatic Gastric Cancer HER2-Targeted Therapy

Patients with metastatic GC were enrolled in Yonsei Cancer Center, Severance Hospital, Seoul, Korea between December 2005 and August 2015. Patients were followed up until December 2016. Patient eligibility criteria were as follows: 1) metastatic GC patients with HER2 positivity defined by either HER2 3+ in immunohistochemical (IHC) staining, or HER2 2+ in IHC staining and HER2 amplification on fluorescence in situ hybridization (FISH) (HER2:CEP17 ratio ≥2); 2) chemotherapy-naive patients with the exception of adjuvant chemotherapy 6 months prior to enrollment; 3) patients who have been treated with palliative trastuzumab in combination with either 5-fluorouracil and cisplatin (FP) or capecitabine and cisplatin (XP). Clinicopathologic parameters were reviewed from the information of the electronic medical record system as previously described [25 (link)].
HER2 status in surgical or biopsy specimen were analyzed and determined by experienced pathologists in Severance Hospital, Seoul, Korea, using the HercepTest Kit™ (DAKO, Denmark) for IHC staining and Vysis™ HER2/CEP FISH probe kit (Abbott, USA) for FISH analysis according to the manufacturers’ instructions. This study was approved by the Institutional Review Board in Severance Hospital, Seoul, Korea (IRB approval number: 4-2014-1076).