Uterine leiomyosarcoma (LMS) is usually diagnosed after surgery for leiomyoma; thus tumor morcellation frequently occurs. We evaluated the impact of tumor morcellation during surgery on the prognosis of patients with apparently early uterine LMS. Outcomes were retrospectively compared between patients who underwent total abdominal hysterectomy without tumor morcellation and those who underwent surgery that included abdominal, vaginal or laparoscopic tumor morcellation. We assessed 56 consecutive patients with stage I and II uterine LMS between 1989 and 2010, 25 with and 31 without tumor morcellation. There were no significant between group differences in age, parity, menopausal status, body mass index, stage, mitotic count, tumor grade, lymph node dissection, adjuvant therapy, and follow-up duration. However, tumor size was significantly smaller (9.8 cm vs. 7.3 cm, P=0.022) and ovarian tissue was more frequently preserved (38.7% vs. 72%, P=0.013) in patients with tumor morcellation. In univariate analysis, only tumor morcellation was significantly associated with poorer disease-free survival (DFS) (odds ratio [OR], 2.59; 95% confidence interval [CI], 1.03-6.50; P=0.043), and higher stage (I vs. II; (OR, 19.12; 95% CI, 1.19-307.11; P=0.037)) and tumor morcellation (OR, 3.07; 95% CI, 1.05-8.93; P=0.040) were significantly associated with poorer overall survival (OS). In multivariate analysis, higher stage (OR, 20.34; 95% CI, 1.27-325.58; P=0.033) and tumor morcellation (OR, 3.11; 95% CI, 1.07-9.06; P=0.038) were significantly associated with poorer OS. The percentage of patients with abdomino-pelvic dissemination, as shown by peritoneal sarcomatosis or vaginal apex recurrence, was significantly greater in patients with than without tumor morcellation (44% vs. 12.9%, P=0.032). Tumor morcellation during surgery increased the rate of abdomino-pelvic dissemination and adversely affected DFS and OS in patients with apparently early uterine LMS. Copyright © 2011 Elsevier Inc. All rights reserved.