RT Journal Article SR Electronic T1 277 Use of preoperative and intraoperative parameters for decision making in ovarian preservation in endometrial adenocarcinoma JF International Journal of Gynecologic Cancer JO Int J Gynecol Cancer FD BMJ Publishing Group Ltd SP A33 OP A33 DO 10.1136/ijgc-2020-ESGO.62 VO 30 IS Suppl 4 A1 Batur, Halise Meltem A1 Gultekin, Murat A1 Salman, Mehmet Coskun A1 Ozgul, Nejat YR 2020 UL http://ijgc.bmj.com/content/30/Suppl_4/A33.1.abstract AB Introduction/Background Oophorectomy which is the integral part of surgery in endometrial adenocarcinoma leads to some adverse effects in premenopausal patients. Therefore, ovarian preservation concept has recently emerged especially in early stage disease. Several studies have shown that such approach does not adversely impact oncologic prognosis. This study aimed to retrospectively investigate the characteristics of endometrial adenocarcinoma patients with ovarian metastasis and to define criteria for ovarian preservation by using preoperative and intraoperative parameters.Methodology Patients with endometrial adenocarcinoma who were operated at Hacettepe University Faculty of Medicine, Department of Obstetrics and Gynaecology were identified. The clinical and pathological characteristics of these patients were reviewed. Following univariate and multivariate analysis to determine factors associated with ovarian spread, different sets of criteria were analyzed to determine the subgroup of patients with no or negligible risk of ovarian metastasis.Results The study group consisted of 725 patients and ovarian metastasis was detected in only 66 (9.1%) of the patients. Univariate analysis showed tumor diameter, grade, histological type, myometrial invasion, peritoneal cytology, lymphovascular space invasion (LVSI), cervical invasion, omental and lymph node metastasis are significantly associated with ovarian metastasis while only LVSI, cervical invasion, omental and lymphatic involvement were significant on multivariate analysis. By using preoperative and intraoperative parameters only, no risk of ovarian metastasis was seen in patients of all ages with endometrioid tumor of any grade without myometrial invasion and risk was negligible (0.7%) among 142 patients (19.6% of study population) of any age with grade 1, endometrioid type tumor without deep myometrial invasion.Conclusion Oophorectomy is not always necessary in endometrial adenocarcinoma. Preoperative and intraoperative uterus-related factors may be used to define patients in whom ovarian preservation is safe similar to the approach used to determine surgical extent. Thus, ovaries may safely be preserved in almost 20% of patients with endometrial adenocarcinoma.Disclosures No potential conflict of interest to declare.