Renal leiomyoma: Case report and literature review.

Renal leiomyomas are rare benign tumours of the kidney originating from muscle cells. They are usually found by an autopsy, whether the patient is asymptomatic or has symptoms (i.e., abdominal/flank pain, hematuria, palpable mass). Today the widespread use of ultrasonography and computed tomography has increased the detection of clinically asymptomatic renal leiomyomas. The differential diagnosis between leiomyomas and other malignant lesions (above all renal cell carcinoma or leiomyosarcoma) is still possible by histological examination. Radiological examinations are not sufficient for the differential diagnosis. Renal leiomyomas have no aggressive behaviour and they usually do not metastasize. The prognosis, after surgery, is excellent without recurrence. We report a case of leiomyoma in a 31-year-old man who presented hematuria and flank pain. We also review the literature and provide a summary of clinical, radiological and histological features of renal leiomyomas.