Prognostic significance of the controlling nutritional status (CONUT) score in patients undergoing gastrectomy for gastric cancer: a systematic review and meta-analysis

Background In recent years, the clinical evidence of the controlling nutritional status (CONUT) score has increased in patients with gastrointestinal cancers. The purpose of this systematic review and meta-analysis was to investigate the association between the preoperative CONUT score and outcomes in patients undergoing gastrectomy for gastric cancer (GC). Methods A systematic literature search for studies reporting the prognostic impact of the CONUT score in patients with GC was conducted. Meta-analyses of survival, postoperative outcomes, and postoperative clinico-pathological parameters were conducted. Results Five studies with 2482 patients were found to be eligible and subsequently reviewed and analyzed. The CONUT score was significantly associated with overall survival (HR 1.85, 95%CI 1.38-2.48, P < 0.001), cancer-specific survival (HR 2.56, 95%CI 1.24-5.28, P = 0.01) and recurrence/relapse-free survival (HR 1.43, 95%CI 1.12-1.82, P = 0.004). Moreover, the CONUT score was associated with the incidence of postoperative complications (OR 1.39, P = 0.003) and mortality (OR 6.97, P = 0.04), and clinico-pathological parameters (T factor [OR 1.75, P < 0.001], N factor [OR 1.51, P < 0.001], TNM stage [OR 1.73, P < 0.001], and microvascular invasion [OR 1.50, P = 0.006]), but not with tumor differentiation (OR 0.85, P = 0.13). Conclusions The preoperative CONUT score is an independent prognostic indicator of survival and postoperative complications, and is associated with clinico-pathological parameters in patients with GC.