Intravascular lipoma of the renal vein

Abstract

Lipomas are benign neoplasms composed of adipocytes encased in a fibrous capsule. Intravascular lipomas are rare and almost always incidental findings. In the published literature, the majority are described within the inferior vena cava (IVC) and less frequently reported in the superior vena cava, brachiocephalic vein, subclavian vein, internal jugular vein, external iliac vein and common femoral vein. We present the case of a 59-year-old male who presented with a symptomatic ureteral calculus and was found to have an intravascular lipoma of the right renal vein with extension into the IVC. To our knowledge, this is the first ever report of an intravascular lipoma in the renal vein. We discuss the imaging characteristics of intravascular lipomas and the differential diagnosis that should be considered.

Mobile primary renal vein lipoma with an accelerated growth pattern

“…Intravenous lipomas are also less frequently reported in several other locations such as the superior vena J o u r n a l P r e -p r o o f cava(SVC) 4 , brachiocephalic 5 , subclavian 6 , common femoral 7 , and external iliac veins 8 . There are only two cases arising from the wall of renal veins, both of which were managed conservatively 2,3 . Differential diagnoses on initial CT included atypical lipoma or liposarcoma.…”

Intravascular lipoma of the inferior vena cava and left renal vein

“…Intravascular lipomas are rare primary venous tumors occurring most commonly in the IVC, with a frequency of 0.35% to 0.5% on all CT scans [12] . A review of the current literature identified isolated case reports of intravascular lipomas of the SVC [3 , 7 , 8] , subclavian vein [2] , innominate vein [6] , internal jugular vein [9 , 10] , femoral vein [4 , 5] , and renal vein [11] . In our patient, two lipomas were present in the IVC and one in the left renal vein.…”

“…Venous lipomas have been less frequently reported in the superior vena cava (SVC), innominate vein, subclavian vein, internal jugular vein, external iliac vein, and common femoral vein [2] , [3] , [4] , [5] , [6] , [7] , [8] , [9] , [10] . Only one case of intravascular lipoma of the right renal vein with extension to the IVC has been reported [11] . To our knowledge, there are no previous reports of multiple isolated lipomas of the IVC and left renal vein.…”

Giant lipoma in superior vena cava: A case report and literature review

“…Intravascular lipomas are composed of adipocytes in a fibrous capsule that have a slow growth rate. It usually shows no symptoms that it commonly diagnosed after an incidental finding [3] . Even though this tumour only caused obstructive symptoms when it has a large size, many had believed that it better be surgically removed due to its probability of causing turbulent blood flow and subsequently thrombotic complication in the venous portal system [4] .…”