Surgical Case Report: Renal Angiomyolipoma with Inferior Vena Cava Involvement

Renal angiomyolipoma (AML) is a benign mesenchymal renal tumor composed of abnormal blood vessels, smooth muscle, and adipose tissue. Although most AMLs are incidentally detected and clinically indolent, large tumors may lead to severe complications. Extension into the Inferior Vena Cava (IVC) is extremely rare and significantly impacts clinical management. We present the case of a 70-year-old woman admitted with acute right upper quadrant abdominal pain and abnormal liver function tests. Contrast-enhanced computed tomography revealed a large right renal mass with macroscopic fat, consistent with angiomyolipoma, associated with a level II tumor thrombus extension into the inferior vena cava and compression of adjacent organs. FDG positron emission tomography showed no pathological uptake, supporting the benign nature of the lesion and excluding the need for preoperative biopsy. After multidisciplinary evaluation, the patient underwent open right nephrectomy with caval thrombectomy. The procedure was performed safely, and the postoperative course was uneventful. Histopathological examination confirmed a classic renal angiomyolipoma without malignant features