The objective of this retrospective multicenter study was to assess the rates, times, and sites of recurrences of 126 patients with uterine leiomyosarcomas. Surgery was the initial therapy for all patients. Median follow-up of survivors was 50 months (range, 3-168 months). Of the 90 patients with stage I-II disease, 26 received postoperative irradiation and/or chemotherapy. Thirty-five (38.9%) patients developed recurrent disease after a median time of 16 months (range, 2-102 months). Recurrence was pelvic in 5 (14.3%) patients, distant in 23 (65.7%), and pelvic plus distant in 7 (20.0%). The overall recurrence rate was similar in patients who received adjuvant treatment and in those who did not. None of the 15 patients who underwent pelvic irradiation developed local recurrences, but 5 of them failed in distant sites. Of the 16 patients with stage III leiomyosarcomas, 2 died of intercurrent disease within 1 month from surgery and 11 received postoperative irradiation and/or chemotherapy. Thirteen patients developed recurrent tumor after a median time of 8 months (range, 1-21 months). Recurrence was pelvic in 3, distant in 4, and pelvic plus distant in 6 patients. Of the 20 patients with stage IV leiomyosarcomas, after surgery 6 were clinically free of disease (group A) and 14 had clinically evaluable residual disease (group B). With regard to group A, 3 patients received postoperative irradiation and/or chemotherapy. Five patients developed recurrent disease after a median time of 11 months (range, 8-16 months). Recurrence was distant in 3 patients and pelvic plus distant in 2. With regard to group B, 11 patients underwent postoperative chemotherapy. Eleven patients died after a median time of 6 months (range, 1-15 months), and 3 are still alive with clinical evidence of disease after 4, 5, and 8 months, respectively, from surgery. Cox model showed that stage (P = 0.0001), mitotic count (P = 0.0002), and age (P = 0.0048) were independent prognostic variables for disease-free survival. In conclusion, uterine leiomyosarcomas have an aggressive clinical behavior, with a propensity to recur both locally and moreover at distant sites. Tumor stage is the strongest prognostic variable. Only patients with early-stage disease have a chance of surviving, whereas the treatment of patients with advanced or recurrent disease is palliative.