The presenting symptoms of leiomyosarcoma (LMS) are the same as those of leiomyoma. The diagnosis of LMS is usually achieved retrospectively after pathological analysis of hysterectomy specimens. The aim of surgery in uterine sarcomas being resection without tumor morcellation, LMS poses the problem of the choice of surgical route because it is more likely to occur in relatively young women. This study was undertaken to determine, firstly, the frequency of LMS in a series of hysterectomies performed for presumed leiomyomas, secondly, if there exist any particular context in which LMS should be considered and how this may modify the choice of surgical route, thirdly, to discuss about the therapeutical aspects of those cases of LMS diagnosed incidentally after uterine morcellation. A retrospective review, from 1996 to 2005, of cases of LMS diagnosed retrospectively in patients having benefited from hysterectomy for presumed leiomyomas, at the department of Obstetrics-Gynaecology, Belfort Hospital. From 1996 to 2005, 1297 hysterectomies have been performed for presumed leiomyomas in our department. Patients' mean age was 48 years (34 to 77 years). Menometrorraghia was the most common symptom having motivated surgery (57%), followed by pelvic pain (31%) and the notion of a rapidly growing uterine mass (12%). The distribution of surgical route was as follows: laparotomic route, n=393 (30%); vaginal route, n=855 (66%) and laparoscopic assisted vaginal route, n=49 (4%). Pathological analysis had revealed LMS in three patients (0.23%). LMS is usually diagnosed incidentally on hysterectomy specimen analysis. Indeed, the surgeon may find himself in a therapeutic dilemma in cases where vaginal extraction has required tumour morcellation with an increased risk of peritoneal and/or vaginal dissemination. However, given the extremely low incidence of LMS in series of hysterectomies performed for presumed leiomyomas and the lack of specific preoperative context to clearly evoke this diagnosis, the fear of leiomyosarcoma should not make us apprehend nonlaparotomic surgical routes.