Nephrectomy and Tumor Thrombectomy with Concurrent Coronary Artery Bypass Graft for an HMB-45-Negative Giant Classical Renal Angiomyolipoma with Venous Extension

Abstract

A 72-year-old woman was found to have a giant right renal mass (11.5 cm) suggestive of an angiomyolipoma (AML) on computed tomography imaging with atypical heterogeneity and grade III tumor thrombus extension into the inferior vena cava (IVC). Significant ischemic heart disease prompted a right radical nephrectomy on cardiopulmonary bypass with tumor thrombectomy and concurrent coronary artery bypass grafts. The patient recovered well and her histopathology confirmed a benign classical (non-epithelioid) renal AML, which was HMB-45 negative. AMLs are benign mesenchymal renal neoplasms, but surgical excision is indicated if malignant characteristics are present on imaging. HMB-45-negative AMLs are exceedingly rare, and to our knowledge, this is the first nephrectomy for an AML of this size and immunohistochemistry profile with IVC extension. Keywords: Renal tumor, nephrectomy, angiomyolipoma