Adjuvant chemotherapy with S-1 plus oxaliplatin improves survival of patients with gastric cancer after D2 gastrectomy: A multicenter propensity score-matched study.

AIM: To investigate the safety and efficacy of S-1 plus oxaliplatin (SOX) as an adjuvant chemotherapy regimen in gastric cancer (GC) after D2 dissection. METHODS: GC Patients who underwent D2 gastrectomy from September 2009 to December 2011 in four Chinese institutions were enrolled. Patients with stage IB-IIIC GC, who received adjuvant SOX treatment were matched by propensity scores with those who underwent surgery alone and those who conducted capecitabine plus oxaliplatin (XELOX) regimen. Disease-free survival (DFS) and overall survival (OS) were compared among the groups. In addition, adverse events in SOX patients were analyzed. RESULTS: Of 1944 GC patients who underwent D2 dissection, 867 were included for analysis. One hundred and seventeen patients treated with SOX were matched to 234 patients who conducted surgery alone. Fifty-seven patients treated with SOX were matched to 57 patients who received XELOX. The estimated five-year DFS was 57.5% in the adjuvant SOX group which was higher than that (44.6%) in the surgery alone group (P = 0.001); and the estimated five-year OS was 68.3% which was higher than that (45.8%) of surgery alone group (P < 0.001). Survival benefit was also revealed in stage III and > 60 years old subgroups (P < 0.001 and P = 0.015, respectively). Compared with XELOX regimen, SOX showed no significant difference in DFS (P = 0.340) and OS (P = 0.361). The most common ≥ 3 grade adverse events of SOX regimen were neutropenia (22.6%), leukopenia (8.9%) and thrombocytopenia (5.6%). CONCLUSION: Compared with surgery alone, SOX regimen significantly improves the long-term survival and has acceptable toxicity in patients with stage IB-IIIC GC after D2 dissection. It may be a novel adjuvant chemotherapy regimen in GC patients.

Association of HER2 status with prognosis in gastric cancer patients undergoing R0 resection: A large-scale multicenter study in China.

AIM: To determine whether the positive status of human epidermal growth receptor 2 (HER2) can be regarded as an effective prognostic factor for patients with gastric cancer (GC) undergoing R0 resection. METHODS: A total of 1562 GC patients treated by R0 resection were recruited. HER2 status was evaluated in surgically resected samples of all the patients using immunohistochemical (IHC) staining. Correlations between HER2 status and clinicopathological characteristics were retrospective analyzed. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox proportional hazard model, stratified by age, gender, tumor location and tumor-node-metastasis (TNM) stage, with additional adjustment for potential prognostic factors. RESULTS: Among 1562 patients, 548 (positive rate = 35.08%, 95%CI: 32.72%-37.45%) were HER2 positive. Positive status of HER2 was significantly correlated with gender (P = 0.004), minority (P < 0.001), tumor location (P = 0.001), pathological grade (P < 0.001), TNM stage (P < 0.001) and adjuvant radiotherapy (74.67% vs 23.53%, P = 0.011). No significant associations were observed between HER2 status and disease free survival (HR = 0.19, 95%CI: 0.96-1.46, P = 0.105) or overall survival (HR = 1.19, 95%CI: 0.96-1.48, P = 0.118) using multivariate analysis, although stratified analyses showed marginally statistically significant associations both in disease free survival and overall survival, especially among patients aged < 60 years or with early TNM stages (I and II). Categorical age, TNM stage, neural invasion, and adjuvant chemotherapy were, as expected, independent prognostic factors for both disease free survival and overall survival. CONCLUSION: The positive status of HER2 based on IHC staining was not related to the survival in patients with GC among the Chinese population.

Associations between interleukin-1 polymorphisms and gastric cancers among three ethnicities.

AIM: To investigate the associations between interleukin (IL)-1B and IL-1RN polymorphisms and gastric cancers among the Tibet, Hui and Han ethnicities. METHODS: Genomic DNA was extracted from peripheral blood of 210, 205, and 202 healthy volunteers and from 155, 158, and 197 gastric cancer patients from the Tibet, Hui, and Han populations, respectively. Polymorphisms in IL-1B and IL-1RN were analyzed by denaturing high-performance liquid chromatography. RESULTS: Carriers of the IL-1B-31 CC genotype had an increased risk of intestinal type gastric cancer [odds ratio (OR) = 2.17, P = 0.037] in the Tibet ethnicity. Carriers of the IL-1B 2/L genotype had an increased risk of both intestinal and diffuse types of gastric cancer (OR = 2.08, 2.31, P = 0.007, 0.016, respectively) in the Hui ethnicity. In the Han population, carriers of the IL-1B-31 CC, IL-1B-511CT, TT genotypes had increased risk of intestinal type gastric cancer (OR = 2.51, 2.74, 5.66, P = 0.005, 0.002, 0.000, respectively). CONCLUSION: IL-1B and IL-RN genotypes may differentially contribute to gastric cancer among the Tibet, Hui, and Han ethnicities in the Qinghai area of China.