In-bag manual versus uncontained power morcellation for laparoscopic myomectomy

Uterine leiomyomas, also referred to as myomas or fibroids, are benign tumours arising from the smooth muscle cells of the myometrium. They are the most common pelvic tumour in women. The estimated rate of leiomyosarcoma, found during surgery for presumed benign leiomyomas, is about 0.51 per 1000 procedures, or approximately 1 in 2000. Treatment options for symptomatic uterine leiomyomas include medical, surgical, and radiologically-guided interventions. Laparoscopic myomectomy is the gold standard surgical approach for women who want offspring, or otherwise wish to retain their uterus. A limitation of laparoscopy is the inability to remove large specimens from the abdominal cavity through the laparoscope. To overcome this challenge, the morcellation approach was developed, during which larger specimens are broken into smaller pieces in order to remove them from the abdominal cavity via the port site. However, intracorporeal power morcellation may lead to scattering of benign tissues, with the risk of spreading leiomyoma or endometriosis. In cases of unsuspected malignancy, power morcellation can cause unintentional dissemination of malignant cells, and lead to a poorer prognosis by upstaging the occult cancer. A strategy to optimise women's safety is to morcellate the specimens inside a bag. In-bag morcellation may avoid the dissemination of tissue fragments.

To evaluate the effectiveness and safety of protected in-bag extracorporeal manual morcellation during laparoscopic myomectomy compared to intra-abdominal uncontained power morcellation.

On 1 July 2019, we searched; the Cochrane Gynaecology and Fertility Group Specialized Register of Controlled Trials, CENTRAL, MEDLINE, Embase, PsycINFO, CINAHL, LILACS, PubMed, Google Scholar, and two trials registers. We reviewed the reference lists of all retrieved full-text articles, and contacted experts in the field for additional and ongoing trials.

We included all randomised controlled trials comparing in-bag extracorporeal manual morcellation versus intracorporeal uncontained power morcellation during laparoscopic myomectomy in premenopausal women.

We followed standard Cochrane methods. Two review authors independently reviewed the eligibility of trials, extracted data, and evaluated the risk of bias. Data were checked for accuracy. The summary measures were reported as risk ratios (RR) or mean differences (MD) with 95% confidence interval (CI). The outcomes of interest were a composite of intraoperative and postoperative complications, operative times, ease of morcellation, length of hospital stay, postoperative pain, conversion to laparotomy, and postoperative diagnosis of leiomyosarcoma. Results for the five main outcomes follow.

We included two trials, enrolling 176 premenopausal women with fibroids, who underwent laparoscopic myomectomy. The experimental group received in-bag manual morcellation, during which each enucleated myoma was placed into a specimen retrieval bag, and manually morcellated with scalpel or scissors. In the control group, intracorporeal uncontained power morcellation was used to reduce the size of the myomas. No intraoperative complications, including accidental morcellation of the liver, conversion to laparotomy, endoscopic bag disruption, bowel injury, bleeding, accidental injury to any viscus or vessel, were reported in either group in either trial. We found very low-quality evidence of inconclusive results for total operative time (MD 9.93 minutes, 95% CI -1.35 to 21.20; 2 studies, 176 participants; I² = 35%), and ease of morcellation (MD -0.73 points, 95% CI -1.64 to 0.18; 1 study, 104 participants). The morcellation operative time was a little longer for the in-bag manual morcellation group, however the quality of the evidence was very low (MD 2.59 minutes, 95% CI 0.45 to 4.72; 2 studies, 176 participants; I² = 0%). There were no postoperative diagnoses of leiomyosarcoma made in either group in either trial. We are very uncertain of any of these results. We downgraded the quality of the evidence due to indirectness and imprecision, because of limited sites in high-income settings and countries, small sample sizes, wide confidence intervals, and few events.

There are limited data on the effectiveness and safety of in-bag morcellation at the time of laparoscopic myomectomy compared to uncontained power morcellation. We were unable to determine the effects of in-bag morcellation on intraoperative complications as no events were reported in either group. We are uncertain if in-bag morcellation improves total operative time or ease of morcellation compared to control. Regarding morcellation operative time, the quality of the evidence was also very low and we cannot be certain of the effect of in-bag morcellation compared to uncontained morcellation. No cases of postoperative diagnosis of leiomyosarcoma occurred in either group. We found only two trials comparing in-bag extracorporeal manual morcellation to intracorporeal uncontained power morcellation at the time of laparoscopic myomectomy. Both trials had morcellation operative time as primary outcome and were not powered for uncommon outcomes such as intraoperative complications, and postoperative diagnosis of leiomyosarcoma. Large, well-planned and executed trials are needed.