Can renal hemangiomas be diagnosed preoperatively?

BACKGROUND Renal hemangiomas are rare benign tumors seldom distinguished from malignant tumors preoperatively. OBJECTIVES To describe the Memorial Sloan-Kettering Cancer Center (MSKCC) experience with diagnosing and treating renal hemangiomas, and to explore possible clinical and radiologic features that can aid in diagnosing renal hemangiomas preoperatively. METHODS Patients with renal hemangiomas treated at MSKCC were identified in our prospectively collected renal tumor database. Descriptive statistics were used to describe the patient characteristics and the tumor characteristics. All available preoperative imaging studies were reviewed to assess common findings and explore possible characteristics distinguishing benign hemangiomas from malignant renal tumors preoperatively. RESULTS Of 6341 patients in our database 15 were identified. Eleven (73%) were males, median age at diagnosis was 53.3 years, and the affected side was evenly distributed. All but two patients were treated surgically. The mean decrease in estimated glomerular filtration rate (eGFR) after surgery was 36.3%; one patient had an abnormal presurgical eGFR and only two patients had a normal eGFR after surgery. We could not identify radiographic features that would make preoperative diagnosis certain, but we did identify features characteristic of hepatic hemangiomas that were also present in some of the renal hemangiomas. CONCLUSIONS Most renal hemangiomas cannot be distinguished from other common renal cortical tumors preoperatively. In select cases a renal biopsy can identify this benign lesion and the deleterious effects of extirpative surgery can be avoided.