The objective of this study is to assess the therapeutic importance of surgical castration, adjuvant hormonal treatment and lymphadenectomy in endometrial stromal sarcoma (ESS). A retrospective and multicentric search was performed. Clinicopathologic data were retrieved from cases that were confirmed to be ESS after central pathology review. The protocol was approved by the Ethical Committee. ESS was confirmed histopathologically in 34 women, but follow-up data were available in only 31 women. Surgical treatment (n=31) included hysterectomy with or without bilateral salpingo-oophorectomy (BSO) in 23 out of 31 (74%) and 8 out of 31 (26%) cases, respectively. Debulking surgery was performed in 6 out of 31 cases (19%). Stage distribution was as follows: 22 stage I, 4 stage III and 5 stage IV. Women with stage I disease recurred in 4 out of 22 (18%) cases. Among stage I women undergoing hormonal treatment with or without BSO, 3 out of 15 (20%) and 1 out of 7 (14%) relapsed, respectively. Among stages III–IV women receiving adjuvant hormonal treatment or not, 1 out of 5 (20%) and 3 out of 4 (75%) relapsed, respectively (differences=55.0%, 95% CI=−6.8–81.2%). Kaplan–Meier curves show comparable recurrence rates for stage I disease without adjuvant hormonal treatment when compared to stages III–IV disease treated with surgery and adjuvant hormonal treatment. Furthermore, women taking hormones at diagnosis have a better outcome when compared to women not taking hormonal treatment. Three out of 31 (9%) patients had a systematic lymphadenectomy whereas 3 out of 31 (9%) had a lymph node sampling. In one case, obvious nodal disease was encountered at presentation. Isolated retroperitoneal recurrence occurred in 1 out of 31 (3%) of all cases and in 1 out of 8 (13%) recurrences. This single woman later also developed lung and abdominal metastases. Leaving lymph nodes in situ does not appear to alter the clinical outcome of ESS. Although numbers are low, the retrospective data suggest that the need for surgical castration (BSO) in premenopausal women with early-stage disease should be discussed with the patient on an individual basis. The data support the current practice in some centres to administer adjuvant hormonal treatment.