The Comprehensive Complication Index versus Clavien-Dindo grading after laparoscopic and open D2-gastrectomy in the multicenter randomized LOGICA-trial

Background: Complications can be classified using the most-severe Clavien-Dindo-Classification (CDC) per patient or the total complication burden per patient expressed in the Comprehensive Complication Index (CCI). This study determined the additional value of CCI to CDC in examining the impact of complications after gastric cancer surgery.Methods: The CCI and CDC were determined in the multicenter randomized LOGICA-trial comparing laparoscopic versus open D2-gastrectomy for cancer (cT1-4aN0-3M0). Differences in median CCI between laparoscopic and open gastrectomy were compared for overall postoperative complications and cardiovascular, gastrointestinal, infectious, pulmonary, and other complications. CCI and CDC were correlated to hospitalization, ICU-stay and reoperations using Spearman's rho-test and compared with standard Fisher's z-transformation.Results: Between 2015 and 2018, 211 patients underwent laparoscopic (n = 106) or open (n = 105) D2-gastrectomy, and 157 (74%) received neoadjuvant chemotherapy. Median CCI was comparable between laparoscopic versus open gastrectomy regarding overall complications (CCI 0 [IQR 0-23.5] versus 0 [IQR 0-22.6]; p = 0.755) and subgroups of complications (p > 0.05). Both CCI and CDC showed moderate positive correlations for hospitalization (r(s) = 0.646 versus r(s) = 0.628; p = 0.001, difference clinically irrelevant), and reoperations (r(s) = 0.590 versus r(s) = 0.599; p = 0.070), and weak correlations for ICU-stay (r(s) = 0.446 versus r(s) = 0.440; p = 0.189).Conclusions: The CCI is a composite scoring system based on the CDC and reflects a subjective interpretation of complication burden from the perspectives of both physicians and patients, following abdominal surgery other than gastrectomy. Implementing CCI showed no clinically relevant benefit and caused additional workload compared to CDC for assessing complication burden. Therefore, using the CCI alongside the CDC after gastric cancer surgery is not recommended.