Development and internal validation of the Comprehensive ALPPS Preoperative Risk Assessment(CAPRA)score

It is with great interest we read the recent study by Capobianco et al.(1),which reported that the Comprehensive Associating Liver Partition and Portal Vein Ligation for Staged Hepatectomy(ALPPS)Preoperative Risk Assessment(CAPRA)score had an impressive ability to predict postoperative mortality before surgery.This study had the largest number of ALPPS patients outside the ALPPS registry,which included 451 patients who underwent ALPPS at 13 centers.The model was constructed on the basis of patient characteristics,underlying disease,and procedure type before Stage 1 of ALPPS.The C statistic was 0.837[95%confidence interval(CI):0.789-0.885],suggesting good discriminatory capacity,which was validated by applying bootstraps and tested on selected subgroups of patients.