TY - JOUR T1 - EP548 Clinicopathologic characteristics and treatment outcomes of Endometrial stromal sarcoma JF - International Journal of Gynecologic Cancer JO - Int J Gynecol Cancer SP - A333 LP - A333 DO - 10.1136/ijgc-2019-ESGO.605 VL - 29 IS - Suppl 4 AU - M-K Kim AU - SC Kim Y1 - 2019/11/01 UR - http://ijgc.bmj.com/content/29/Suppl_4/A333.1.abstract N2 - Introduction/Background Endometrial stromal tumors are rare uterine sarcomas, comprising low-grade endometrial stromal sarcoma (ESS) and undifferentiated endometrial sarcoma (UES). This study evaluated their clinicopathologic characteristics and clinical outcomes.Methodology A retrospective analysis was performed on 18 patients with histologically proven endometrial stromal tumors who were treated and followed-up at a single Korean institution from 2004 to 2015.Results Thirteen patients were diagnosed with low-grade ESS and 5 patients had UES. The mean ages at diagnosis of ESS and UES patients were 46.2 and 45.2 years, respectively. Preoperative diagnosis through curettage or hysteroscopic endometrial biopsy was made in 30.8% and 80% in ESS and UES, respectively. Vaginal or laparoscopically-assisted hysterectomy was performed in 6 patients (46.2%) with stage I ESS, of whom there was no recurrence with a median follow-up period of 33.6 months. Lymph node dissection was performed in 61.5% and 60% of ESS and UES patients, and only 1 ESS patient (7.7%) showed microscopic lymph node metastasis. Although the stage distribution was similar between ESS and UES patients, 5-year progression-free survivals were 77.9% and 40% for ESS and UES patients, respectively. The sites of recurrence were loco-regional in ESS patients, whereas UES patients recurred mainly in the distant sites, such as lung. The performance of lymphadenectomy, adnexectomy, or adjuvant treatments was not associated with decreased recurrence rate.Conclusion The two endometrial stromal tumors, ESS and UES, show different clinical outcomes despite similar initial presentations. Patients with UES tend to recur at distant sites even in the early stage. On the contrary, ESS show favorable prognosis with longer PFS. In the selected cases of low-grade ESS with small tumor size and without extrauterine involvement, laparoscopic staging also seems to be feasible.Disclosure Nothing to disclose. ER -