Patients who have undergone supracervical hysterectomy or uterine morcellation for presumed benign uterine disease and are found to have malignancy on final pathology represent a management dilemma. Our goal was to analyze our experience and make observations regarding staging, treatment, and outcomes. We performed a retrospective case series of patients referred to our institution with uterine malignancy who previously underwent supracervical hysterectomy or uterine morcellation at the time of original surgery for presumed benign uterine disease. Between January 2000 and March 2006, 17 patients with uterine malignancy were identified. Following initial surgery, 15 (88%) patients had presumed stage I disease and 2 (12%) patients had stage III disease. Two (15%) of 13 patients who underwent completion surgery were upstaged; both had leiomyosarcoma (LMS) originally resected with morcellation. Ten of 11 patients whose stage was confirmed with secondary surgery remain disease free. None of the patients who initially underwent supracervical hysterectomy without morcellation were upstaged by secondary surgery. The median follow-up interval was 30 months (range, 2-90 months). Reoperation for completion surgery and staging is important when uterine malignancy is found incidentally after morcellation or supracervical hysterectomy for presumed benign uterine disease. Approximately 15% of patients will be upstaged by reexploration, particularly those with LMS who underwent morcellation. Patients who undergo completion surgery with restaging and are not upstaged appear to have a good prognosis. Surgical staging is valuable for prognosis and may alter postoperative treatments.