<h4>Purpose</h4>Hereditary Leiomyomatosis and Renal Cell Cancer (HLRCC) is a hereditary cancer syndrome associated with germline pathogenic variants of the fumarate hydratase (FH) are at risk for the development of benign renal cysts as well as an aggressive form of renal cell carcinoma which can occur inside the cysts. The gene discussed is FH; the disease is renal cell carcinoma.