A Case Report of a Giant Renal Angiomyolipoma Complicated by Perinephric Hematoma in a Patient With Tuberous Sclerosis.

Tuberous sclerosis (TSC) is an autosomal dominant neurocutaneous disorder where pathogenic variants cause overactivation of the rapamycin (mTOR) pathway, leading to tumor formation. These benign tumors, or hamartomas, occur in multiple organs, including the brain, skin, eyes, kidneys, lungs, and liver. Renal angiomyolipomas (AMLs) occur frequently in TSC and are highly vascular tumors primarily composed of blood vessels, smooth muscle, and mature adipose tissue. Renal AMLs greater than 10 cm are rarely seen and are considered "giant" AMLs. Everolimus, an mTOR inhibitor, is a treatment option to slow the growth of renal AMLs. Renal tumors, especially renal AMLs, are the most common cause of perinephric hematomas. For renal AMLs with a high risk of bleeding, embolization can be used to delay renal decline. We present the case of a young patient with a history of TSC complicated by bilateral renal AMLs that required right-sided nephrectomy and chronic kidney disease stage four who presented with progression of her known left-sided renal AML to giant status and perinephric hematoma following both everolimus treatment and multiple embolizations. The purpose of this case report is to reinforce the importance of routine oncology follow-up to prevent the progression of renal AMLs and to highlight the multidisciplinary approach of multiple specialties to preserve the quality of life and renal function of our young patient with a rarely reported "giant" AML.