Retrograde growing intravenous leiomyomatosis-a case report.

Background: Leiomyomatosis is a benign tumor that usually originates from smooth muscle cells and can appear at any location. Intravenous leiomyomatosis (IVL) usually grows along blood vessels and extends toward the iliac vein and the inferior vena cava (IVC). It extends toward the right heart cavity and the main pulmonary artery in extreme cases. IVL is a rare smooth muscle tumor that is histologically benign but clinically aggressive. It is not typical for IVL to develop metastases, but rather to grow progressively and cause mechanical compression in surrounding. Case Description: We report a case of retrogradely growing IVL, originating in the uterus and extending along the venous system to the right heart. At the same time, this leiomyomatosis retrogrades into the right external iliac vein. A 48-year-old woman with a mass in the IVC was admitted to Wuhan Union Hospital. She had undergone a hysterectomy for fibroids 2 years previously. Computed tomography venography and three-dimensional reconstruction revealed filling defects in the IVC, right internal and external iliac veins, right common iliac vein, right renal vein, and right atrium. After a multidisciplinary consultation, IVC leiomyomatosis was considered, and surgical treatment was performed. Conclusions: We report a case of retrogradely growing IVL. It originates in the uterus, extends along the venous system to the right internal iliac vein, and grows retrogradely into the external iliac vein. This is a new growth path that has rarely been mentioned.