Systemic inflammation score: a novel risk stratification tool for postoperative outcomes after video-assisted thoracoscopic surgery lobectomy for early-stage non-small-cell lung cancer

OBJECTIVES: To evaluate whether the systemic inflammation score (SIS) could predict postoperative outcomes for patients undergoing video-assisted thoracoscopic surgery (VATS) lobectomy for early-stage non-small-cell lung cancer (NSCLC). METHODS: This retrospective study was conducted on the prospectively maintained database in our institution between January 2016 and December 2017. Preoperative SIS comprising serum albumin (sALB) and lymphocyte-to-monocyte ratio (LMR) was graded into 0, 1 and 2, and then utilized to distinguish patients at high surgical risks. Multivariable logistic-regression analysis was conducted to determine independent risk factors for postoperative outcomes. RESULTS: There were 1,025 patients with TNM-stage I-II NSCLC included, with an overall morbidity rate of 31.1% and mortality rate of 0.3%. We applied the sALB at 40 g/L and the median LMR of our series at 4.42 as dichotomized cutoffs for modified SIS scoring criteria. Both minor and major morbidity rates in patients with SIS=2 were significantly higher than those in patients with SIS=0 and with SIS=1 (P<0.001). No difference was found in overall morbidity rate between patients with SIS=1 and with SIS=0 (P=0.20). No significant difference was found in the mortality rate between these 3 groups. Patients with SIS=2 had the highest probability to experience most of individual complications. Finally, multivariable logistic-regression analysis suggested that preoperative SIS=2 could independently predict the morbidity risks following VATS lobectomy (OR=1.73; 95% CI=1.11–2.71; P=0.016). CONCLUSIONS: The SIS scoring system can be employed as a simplified, effective and routinely operated risk stratification tool in patients undergoing VATS lobectomy.