Development of a postoperative risk scoring tool for elderly patients with early gastric cancer: an exploratory prognostic score derivation study.

BACKGROUND: Elderly patients with early gastric cancer (EGC) represent a clinically challenging and growing surgical population. Compared to advanced gastric cancer (AGC), the evidence available for this population is limited. As such, no validated composite risk scoring tool currently exists for postoperative risk stratification in this population. Therefore, this study aimed to identify the negative prognostic factors for long-term survival that may be used for developing a risk scoring tool for elderly EGC patients undergoing curative gastrectomy. METHODS: This retrospective single high-volume tertiary center study enrolled patients aged 75 years or older who underwent curative gastrectomy for histopathologically confirmed stage I gastric cancer between January 2007 and December 2016. Univariable and multivariable Cox proportional hazard regression analyses were performed using more than ten variables, including age, sex, Prognostic Nutritional Index (PNI), Charlson Comorbidity Index (CCI), preoperative hemoglobin level, and extent of gastrectomy. The 5-year overall survival (OS), assessed by the Kaplan-Meier method with log-rank testing, was the primary endpoint. A composite risk score was derived by assigning one point per independently significant risk factor. RESULTS: 534 patients were enrolled with a mean age of 77.6±2.8 years. 366 patients (68.5%) were male and 450 (84.3%) underwent distal gastrectomy. The age-independent CCI was 3 or higher in 155 patients (29.0%), and preoperative anemia was present in 213 patients (39.9%). Multivariable analysis identified five independent negative prognostic factors: age ≥80 years [hazard ratio (HR) 2.0, 95% confidence interval (CI): 1.3-3.1; P=0.002], male sex (HR 2.1, 95% CI: 1.2-3.7; P=0.009), CCI ≥3 (HR 1.6, 95% CI: 1.1-2.4; P=0.03), preoperative anemia (HR 1.7, 95% CI: 1.1-2.6; P=0.01), and total gastrectomy (HR 2.0, 95% CI: 1.3-3.2; P=0.003). A composite risk score (range, 0-5) stratified patients into low-risk (score 0-1; n=252), intermediate-risk (score 2; n=184), and high-risk (score ≥3; n=98) groups. 5-year OS rates were 91.2%, 82.5%, and 61.2%, respectively (P<0.0001). The 5-year OS for the entire cohort was 82.7%. CONCLUSIONS: This composite risk score stratifies postoperative risk in elderly patients with EGC by predicting long-term survival according to each risk category. In selected high-risk elderly patients with EGC, future prospective evaluation of less invasive or function-preserving surgical strategies is warranted.