Objective: The aim of this study is to identify the prognostic significance of X-ray cross-complementing gene 1 (XRCC1) in patients with gastric cancer undergoing surgery and platinum-based adjuvant chemotherapy.
Methods: Immunohistochemistry (IHC) was used to evaluate XRCC1 protein expression profiles on surgical specimens of 612 gastric cancer patients. The relationship between XRCC1 expression and existing prognostic factors, platinum-based adjuvant chemotherapy, disease-free survival (DFS) and overall survival (OS) were analyzed.
Results: Among 612 patients staged II/III in our study, 182 (29.74%) were evaluated as XRCC1 IHC positive. XRCC1 expression was not significantly related to OS (P=0.347) or DFS (P=0.297). Compared with surgery only, platinum-based adjuvant chemotherapy significantly improved the OS (P=0.031). And the patients with negative XRCC1 expression benefited more from platinum-based adjuvant chemotherapy (P=0.049). Multivariate analysis demonstrated that tumor size, T category, N category, vascular or nerve invasion and platinum-based chemotherapy were good prognostic factors for OS (P<0.05). Though XRCC1 plays an important role in DNA repair pathways, no significant relationship is found in XRCC1 expression and OS among gastric cancer in our study.
Conclusions: XRCC1 might be an alternative prognostic marker for the patients of gastric cancer after radical resection. The patients with negative XRCC1 expression can benefit more from platinum-based adjuvant chemotherapy.

Keywords: Gastric cancer; X-ray cross-complementing gene 1 (XRCC1); platinum drugs prognosis