Ultrasound appearance of intravenous leiomyomatosis: A case report

Intravenous leiomyomatosis (IVL) is a rare benign smooth muscle tumor that can develop from the pelvic or uterine veins and spread into the central veins and heart. Here, we report a case of recurrent IVL in a 48-year-old woman. To the best of our knowledge, this is the first case report of IVL that describes the characteristic ultrasound features of the tumor, including the rainbow sign.

A 48-year-old woman developed a solid-cystic lesion in the inferior vena cava (IVC) 3 years after undergoing a right heart tumor resection and 5 years after undergoing hysterectomy.

Physical examination was unremarkable. However, ultrasonography showed a solid-cystic lesion in the IVC, and a diagnosis of IVL was made.

The patient underwent complete surgical removal of the tumor by a multidisciplinary team. The tumor was resected successfully.

Pathological examination confirmed that the IVC tumor thrombus was consistent with IVL. During follow-up, there were no signs of local or distant recurrence.

The preoperative diagnosis of IVL is difficult, and the tumor is usually misdiagnosed as a thrombus or right atrial myxoma. A thorough understanding of the characteristic imaging features of IVL is essential for an accurate preoperative diagnosis. The lesion in our patient showed multiple tracts, a honeycomb appearance, and vividly colorful blood flow that resembled a rainbow, which we termed the rainbow sign.