Intravenous leiomyomatosis

Associate Editor-In-Chief:

Overview

 * Intravenous leiomyomatosis (IVLM) is characterized by the extension into venous channels of histologically benign smooth muscle tumor arising from either the wall of a vessel or from a uterine leiomyoma.
 * Fewer than 100 cases have been reported in all, and only 14 cases involved intracardiac extension from the IVC.
 * In one reported case, this slowly growing invasive neoplasm extended not only into the heart but into both pulmonary arteries as well.

Etiology

 * The etiology of IVLM is unclear. All described patients are female, and most are white, premenopausal, and parous.
 * The median age is 45 years, with patients ranging from 26 to 70 years old.
 * The patients may be asymptomatic or have symptoms of uterine leiomyomas.
 * Patients with obstruction of the right atrium may present with syncopal episodes, dyspnea on exertion, shortness of breath, etc.
 * The tumor is slow growing, and the prognosis is favorable.

Differential Diagnosis

 * When the IVC is involved the differential diagnosis should include renal malignancies and primary leiomyoma or sarcoma, as well as thrombosis of the IVC.
 * IVLM should be considered in young women with cardiac symptoms who have a right atrial mass as well as a pelvic mass or who have previously undergone hysterectomy for leiomyoma uterus with intravenous involvement.

Complications

 * Although embolization of the tumor represents a theoretical risk, this has not been reported.
 * The tumor can recur, and repeat operation may be necessary.
 * Most reported deaths involved extension of the tumor into the heart, with death due to mechanical obstruction rather than the neoplastic process per se


 * Intravenous leiomyomatosis should not be confused with benign metastasizing leiomyoma, in which a benign uterine leiomyoma is associated with a benign smooth muscle tumor located in the parenchyma of a distant organ, such as lung.
 * Intravenous leiomyomatosis is confined to vessels, whereas benign metastasizing leiomyoma shows no relation to vascular channels.

Example #1
Patient presented with S.O.B. one year after hysterectomy for a leiomyomatous uterus (Images shown below are courtesy of RadsWiki and copylefted}