RT Journal Article SR Electronic T1 2022-RA-1456-ESGO Ovarian cancer metastases in the liver area: a retrospective analysis of surgical, intraoperative and postoperative outcomes according to a standardize anatomo-surgical classification JF International Journal of Gynecologic Cancer JO Int J Gynecol Cancer FD BMJ Publishing Group Ltd SP A338 OP A339 DO 10.1136/ijgc-2022-ESGO.720 VO 32 IS Suppl 2 A1 Rosati, Andrea A1 Pavone, Matteo A1 de Palma, Antonella A1 Conte, Carmine A1 Ghirardi, Valentina A1 de Rose, Agostino Maria A1 Giuliante, Felice A1 Scambia, Giovanni A1 Fagotti, Anna YR 2022 UL http://ijgc.bmj.com/content/32/Suppl_2/A338.3.abstract AB Introduction/Background We recently developed an anatomo-surgical classification for ovarian cancer (OC) metastases in the liver area consisting in 5 different types (Type-1:Glisson’s,Type-2:Ligamentous,Type-3:Gallbladder,Type-4:Hepatic hilum,Type-5:Liver parenchymal).This study aims to evaluate whether this classification is able to identify patients at greater risk of intra and postoperative complications and with increased surgical complexity.Methodology All epithelial advanced-OC patients who underwent primary or secondary surgery with perihepatic liver involvement were retrospectively retrieved.Patients were classified according to our published anatomo-surgical classification and further clustered into four major Classes:Class-I or ‘Peritoneal’ (including Type1,2,3), Class-II or ‘Hepatoceliac lymph-nodes’(Type-4), Class-III or ‘Parenchymal’(Type-5) and Class IV or Mixed (≥2 classes).Results 615 patients were identified, and Class I resulted as the most commonly represented (337 cases, 54.8%).The distribution of surgical complexity score (SCS) was superimposable among classes (p=0.239) while operative time and estimated blood loss were significantly longer/higher in Class IV (Mixed) (p<0.001). Intraoperative transfusions were more frequent in Class IV (30.4%) and less reported in Class-III (11.9%) (p=0.004); vascular injuries were significantly grouped in Class II (8%) (p=0.009).Class II and IV were more frequently associated to severe postoperative complications (p=0.008). Moreover, specific complications were found in each Class: perihepatic collection and intrahepatic hematoma/abscess in Class-III (respectively: p=0.003, p>0.001); pleuric effusion, sepsis, anemia and ‘other complications’ in Class IV (respectively: p=0.002, p=0.004, p=0.03, p=0.03).At Multivariate analysis SCS 3 and macroscopic residual tumor were identified as risk factors for severe postoperative complications (respectively: OR: 3.922, p=0.003 and OR: 1.748, p=0.048).Conversely, Class-I and III resulted to be at decreased risk for severe postoperative complications compared to Class IV.Abstract 2022-RA-1456-ESGO Figure 1 Conclusion Our classification represents a useful and reliable tool, able to stratify patients with OC metastases in the liver area in Classes with different surgical outcomes and different postoperative complication profile.