Natural history of leiomyomas beyond the uterus.

Rationale: Most leiomyomas are located in the uterus. Leiomyomas are rarely found outside the uterus and classified as leiomyoma beyond the uterus (LBU). This group consists of disseminated peritoneal leiomyomatosis, benign metastasizing leiomyoma, intravenous leiomyomatosis, parasite leiomyoma located in the broad ligament and retroperitoneal space. The descriptions of the patients who suffer from these types of leiomyomas are presented mainly in case reports.

Patient Concerns: A 34-year-old multiparous woman was operated on multiple recurrent uterine leiomyoma in parametrium. At one time, 32 leiomyomas were removed. Thirteen months following it, in next laparotomy, 132 leiomyomas were excised. Histologically, both were intravenous leiomyomas (IVLs).

Diagnosis And Interventions: In follow-up, computed tomography (CT) and magnetic resonance imaging scans were performed to look for next recurrent leiomyoma. Accidentally, the mass was found in inferior vena cava which was diagnosed as intravenous vena cava leiomyoma. The mass was removed and the final diagnosis of intravenous myoma was confirmed in histopathology.

Outcomes: CT scan performed 3 months after the surgery for leiomyoma in vena cava revealed no pathology. Next 10 months' follow-up was uneventful.

Lessons: The recurrent multiple uterine leiomyoma precede LBU. The uterine leiomyoma spreads intravenously route to parametria as parasite leiomyoma, then to vena cava. It has to be taken into account in follow-up.