HER-2 expression in advanced gastric cancer and its correlation with clinical features, outcome and prognosis

Abstract

To assess the HER-2 status in Chinese advanced gastric cancer patients and explore its correlation with clinical features, treatment response and prognosis. A total of 107 patients with advanced gastric cancer treated in our hospital from December 2005 to November 2008 were included in this retrospective analysis. HER-2 status was determined by immunohistochemisty (IHC) and/or fluorescence in situ hybridization (FISH). The correlations of HER-2 status with tumor location, pathology, treatment response and prognosis were analyzed and the efficacy of different chemottherapy regimens was compared. The overall positive rate of HER-2 expression was 14.7% (15/102). The HER-2 status was detected by both methods in 102 patients, and the concordance of the two methods was 66.5%. The tumor site distribution was gastroesophageal junction (GEJ) 28.0%, proximal stomach 19.4%, gastric corpus 16.1%, antrum 26.9% and whole stomach 9.7%, respectively. There was no significant difference of HER-2 status among different tumor sites (P = 0.726), and no significant correlation between HER-2 expression and differentiation (P = 0.110). Among the evaluable 51 patients treated by first-line chemotherapy, the total objective effective rate was 23.5%. The median time-to-progression was 7.47 months, and median overall survival time was 11.07 months. The effective rate was 43.8% in patients who received XP regimen chemotherapy (cisplatin + capecitabine), significantly higher than the 14.3% in patients treated with other regimens (P = 0.033). Their overall survival was 14.17 months and 9.53 months, respectively (P = 0.059). The TTP was 6.63 months in HER-2 positive patients and 7.47 months in HER-2 negative patients, with a non-significant difference (P = 0.510). However, there was a improving tendency in the efficacy and OS, showing a effective rate of 45.5% and 17.5% (P = 0.102) and OS of 14.17 months and 10.63 months, respectively (P = 0.205). HER-2-positivity rate in Chinese patients with advanced gastric cancer is similar to those reported in the literature. Along with the increasing use of targeted therapy and targeted agents, the efficacy and survival of gastric cancer patients is improving. HER-2-positive patients may benefit from it.