A case report of transcatheter arterial embolization for extra-renal retroperitoneal angiomyolipoma associated with tuberous sclerosis complex.

An 83-year-old male who underwent left nephrectomy about 40 years ago presented with a fatty mass in the retroperitoneum on CT images. The patient was diagnosed with extra-renal retroperitoneal angiomyolipoma (AML) through CT-guided retroperitoneal biopsy. Based on additional tests, the patient was also diagnosed with tuberous sclerosis complex (TSC). Given the substantial size (over 4 cm) of the tumor and the presence of an aneurysm, transcatheter arterial embolization (TAE) was performed to prevent rupture. Transcatheter embolization of the left testicular artery, left inferior phrenic artery, and left first lumbar artery did not result in any major complications. In addition, the tumor size had significantly reduced 12 months after TAE, and no aneurysm was detected. Extra-renal retroperitoneal AMLs associated with TSC are extremely rare, and may involve more feeding arteries than renal AMLs. Given the challenges in performing emergency TAE for ruptured extra-renal retroperitoneal AMLs, it is preferable to prevent rupture using this approach.