Incidence and risk factors of parasitic myoma after laparoscopic myomectomy using uncontained power morcellation: Retrospective analysis of 87 patients who had a subsequent second laparoscopic surgery.

ABSTRACT

AIM: Studies on parasitic myomas after laparoscopic morcellation are mainly limited to case reports, and the incidence and risk factors have not yet been well-understood. We aimed to clarify the actual incidence and risk factors of parasitic myoma after laparoscopic myomectomy using uncontained power morcellation by reviewing cases with subsequent laparoscopic surgery. METHODS: This retrospective study included 87 patients who had laparoscopic myomectomy using uncontained power morcellation, followed by subsequent second laparoscopic surgery for gynecological disease between 2008 and 2021. First, the incidence and characteristics of parasitic myomas detected at the second laparoscopic surgery were reviewed. Second, patients were stratified according to the presence of parasitic myoma (PM+ and PM- groups), and risk factors were analyzed by comparing the background, intraoperative findings, and clinical course after laparoscopic myomectomy. RESULTS: Of the 87 patients, parasitic myomas were detected in 16 (18.4%). Twelve patients (75.0%) were asymptomatic and diagnosed incidentally during surgery. Two patients presented with acute abdomen requiring emergency surgery. Comparing the PM+ and PM- groups, the total weight of the enucleated myomas and the diameter of the largest myoma at the initial laparoscopic myomectomy were significantly greater in the PM+ group. Other factors, including age and number of enucleated myomas did not differ between the groups. CONCLUSIONS: The actual incidence of parasitic myoma after laparoscopic myomectomy using uncontained power morcellation is higher than that previously reported. In laparoscopic power morcellation, large myomas increase the risk of developing parasitic myoma, and a containment bag system is expected to minimize this complication.