OC08.05: *The efficacy of preoperative ultrasound in detecting uterine sarcoma prior to myomectomy

Abstract

The prevalence of leiomyosarcoma is estimated at 0.12 per 1000 surgeries. We investigated the efficacy of preoperative ultrasound in detecting uterine sarcoma and selecting women who are suitable for laparoscopic myomectomy. This is a retrospective review of myomectomies performed between January 2004 and June 2014 in a single surgical unit. Laparoscopic myomectomy was offered to women with ≤3 intramural/submucous myomas and a dominant myoma measuring 5-12cm. The remaining women were offered open myomectomy. Ultrasound findings suggestive of sarcoma were: irregular shaped tumours, blurred margins, necrosis, peritoneal deposits and inability to visualise the endometrial cavity. These women were referred to gynecological oncologists for further management. There were 1261 women presenting with symptomatic fibroids requiring surgery. 17 (1.3%) were diagnosed with uterine sarcoma. 903 women requested abdominal myomectomy. 514/903 (56.9%) of them were scheduled for laparoscopy and 389/903 (43.1%) women had open myomectomy. Final histology confirmed a sarcoma in 12/17 (70.6%) women with ultrasound diagnosis of malignancy. In addition, 1/389 (0.3%) women who had an open myomectomy had sarcoma on histology, compared to 1/514 (0.2%) women who were booked for laparoscopic myomectomy. In the latter case, the diagnosis of sarcoma was made at surgery and an open hysterectomy was performed instead. The sensitivity of ultrasound diagnosis of uterine sarcoma was 85.7% (95% CI 57.2 - 98.2) and the specificity was 99.5% (95% CI 98.7 - 99.8). Preoperative ultrasound diagnosis of uterine sarcoma is highly specific. The sensitivity was less than 90% and additional precautions such as in-bag morcellation should be employed to avoid inadvertent peritoneal spread of undiagnosed malignancies.