Involvement in the tumor-infiltrating CD8(+) T cell expression by the initial disease of remnant gastric cancer

Background Remnant gastric cancer (RGC) has been increasing for various reasons such as a longer life span, medical progress, and others. It generally has a poor prognosis, and its mechanism of occurrence is unknown. The purpose of this study was to evaluate the clinicopathological features of and clarify the oncological features of RGC. Methods Between January 2002 and January 2017, 39 patients with RGC following distal gastrectomy underwent curative surgical resection at the Okayama University Hospital; their medical records and immunohistochemically stained extracted specimens were used for retrospective analysis. Results On univariate analysis, initial gastric disease, pathological lymph node metastasis, and pathological stage were the significant factors associated with poor overall survival (p=0.014, 0.0061, and 0.016, respectively). Multivariate analysis of these 3 factors showed that only initial gastric disease caused by malignant disease was an independent factor associated with a poor prognosis (p=0.014, hazard ratio: 4.2, 95% confidence interval: 1.3-13.0). In addition, tumor-infiltrating CD8(+) T cells expression was higher in the benign disease group than in the malignant group (p=0.046). Conclusions Initial gastrectomy caused by malignant disease was an independent poor prognostic factor of RGC, and as one of the causes, lower level of tumor-infiltrating CD8(+) T cells in RGC may involve in.