Multimodality Evaluation of Intravenous Leiomyomatosis: A Rare, Benign but Potentially Life-Threatening Tumor

BACKGROUND Intravenous leiomyomatosis (IVL) is a rare tumor, which is usually of uterine origin, characterized by intravascular nodular masses of histologically benign smooth muscle that may extend variable distances, including into the inferior vena cava, right atrium and pulmonary arteries. Tumors may arise from uterine leiomyoma, walls of the uterine vessel, or myometrium. It usually occurs at between 20-70 years of age with a median age of 45 years. The most commonly affected women are pre-menopausal and multiparous. Intra-cardiac extension may represent a diagnostic challenge as it is usually misdiagnosed as a right atrial myxoma and may cause multiple symptoms, such as shortness of breath, tachycardia, chest pain, syncope, and even death. CASE REPORT We present the case of a 40-year-old female patient with past medical history of arterial hypertension, who was referred to a cardiovascular center due to an intra-cardiac mass found on 2D echocardiogram. The patient was given the rare diagnosis of intravenous leiomyomatosis of the uterus with extension into the gonadal veins, inferior vena cava, right atrium, right ventricle, and main pulmonary arteries. Imaging workup including trans-esophageal echocardiogram, cardiac catheterization, contrast-enhanced abdomen and pelvic CT scans, and cardiac MRI was performed for evaluation. CONCLUSIONS Intravenous leiomyomatosis is a rare diagnosis that merits consideration in a young pre-menopausal female patient with cardiac symptoms associated with a right atrial mass. Radiologists play a vital role in the diagnosis and follow-up of patients with the diagnosis of intravenous leiomyomatosis. Differential diagnosis includes vascular thrombus as well as primary and metastatic tumors. Early detection is imperative for appropriate treatment and surgical planning.