Hereditary Leiomyomatosis and Renal Cell Cancer (HLRCC) Syndrome.

In hereditary leiomyomatosis and renal cell carcinoma syndrome, fumarate hydratase-deficient renal cell carcinomas typically present as aggressive, unilateral, often cystic masses with heterogeneous enhancement. These tumors can metastasize early, making appropriate imaging and staging critical for diagnosis and management. Teaching point: When a renal lesion suspected of RCC is identified in a patient with cutaneous and uterine leiomyomas, HLRCC should be evaluated, which is important for future genetic counseling.