This sort of leiomyoma likely originates as a pedunculated subserosal leiomyoma that twists and torses from its uterine pedicle. The contact with the uterus is then lost.
Once free in the peritoneal cavity, it then survives by recruiting neo-vascularization from adjacent structures. The originating pedunculated fibroid likely develops pre-menopausally, whereas the parasitic leiomyoma may become clinically evident either before or after menopause.
Occasionally a broad ligament leiomyoma is also classified under parasitic leiomyomas .
On imaging, a parasitic leiomyoma presents as a solid pelvic or abdominal mass with characteristics similar to uterine leiomyoma.
Treatment and prognosis
With behavior similar to uterine leiomyoma, a parasitic leiomyoma may recur after resection or, conversely, may show hormone-responsive behavior, including size stability or even shrinkage with natural, surgical, or chemical menopause.
Surgery is usually performed for symptomatic relief or to prevent impingement of vital structures.
The differential for a parasitic leiomyoma varies with its location can include: