PT - JOURNAL ARTICLE AU - C Tauste Rubio AU - S Aguirre Gorospe AU - J Zabaleta Jurío AU - M Ruiz García AU - I Zabaleta Loinaz AU - JC Muruzábal Torquemada TI - EP462 Value of tumor markers and pelvic mass diameter in differential diagnosis of peritoneal carcinomatosis AID - 10.1136/ijgc-2019-ESGO.521 DP - 2019 Nov 01 TA - International Journal of Gynecologic Cancer PG - A294--A295 VI - 29 IP - Suppl 4 4099 - http://ijgc.bmj.com/content/29/Suppl_4/A294.short 4100 - http://ijgc.bmj.com/content/29/Suppl_4/A294.full SO - Int J Gynecol Cancer2019 Nov 01; 29 AB - Introduction/Background Peritoneal Carcinomatosis (PC) is a late stage manifestation of several malignancies like gynecological, gastrointestinal or hepatobiliary cancers, among others. Epithelial ovarian cancer (EOC) is the most common cause in women and has better outcomes in terms of survival compared with other malignanciess like colorectal neoplasms or mesotheliomas. The pathological study is essential to plan the suitable treatment and early intervention in EOC. In this work we analyzed the value of tumor markers CA 125, CEA, ratio CA 125/CEA and diameter of ovarian tumor (DOT) as a pre-surgical predictive tool of ovarian cancer.Methodology We recruited patients with suspicious CP studied in the Gynaecological Department of Complejo Hospitalario de Navarra, between 2005 and 2016. CA 125 and CEA were evaluated in preoperative venous blood samples and DOT was estimated by ultrasound or CT scan.Results We identified 250 patients with suspicious CP. Median age was 64,5 years and most patients (86.4%) were diagnosed with EOC. Final diagnosis is described in table 1. CA 125 and ratio CA 125/CEA was higher in those patients with EOC, while CEA was lower with significant differences (p<0,05). DOT was similar in both groups without signficant differences (figure 1). Receiver-operating curve (ROC) analysis showed low power diagnostic in EOC patients for CA 125 and CEA (Area under the curve, AUC: 0.698 and 0.642 respectively). ROC analysis of CA 125/CEA ratio improves the results (AUC: 0,747) (figure 2).Conclusion CA 125, CEA and CA 125/CEA ratio showed certain utility to guide the diagnosis of EOC in CP. However the cut-off levels of this study did not show clinical relevance. DOT did not prove any additional information. Other techniques, such as HE 4 or Thermal liquid biopsy could be more specific for EOC.Disclosure Nothing to disclose.View this table:Abstract EP462 Table 1 Final diagnosis of peritoneal carcinomatosisView this table:Abstract EP462 Table 2 Area Under the Curve (AUC), Specificity and Sensitivity of CA 125, CEA, CA 125/CEA ratio and Diameter of Ovarian Tumor (DOT)Abstract EP462 Figure 1 Stem-and-Leaf Diagram of CA 125, CEA, CA 125/CEA ratio and Diameter of Ovarian TumorAbstract EP462 Figure 2 Receiver Operating Characteristic curve (ROC) of CA 125, CEA. CA 125/CEA ratio, DOT