Primary leiomyosarcoma of kidney with metastasis to contralateral kidney. Case report.

Introduction: Renal leiomyosarcoma is a rare entity in the world and its understanding is based on reports and various cases; however, the prognosis is bleak for its malignant potential and an average survival of 18 months.

Clinical case: A 54-year-old woman with a clinical picture of 6 months of pain in the right flank and a tomographic image of a bilateral renal lesion underwent right radical nephrectomy and left conservative surgery. The definitive histopathological study reported right primary renal leiomyosarcoma with left metastasis.

Conclusion: Renal leiomyosarcoma is an entity of low incidence and high mortality; however, our case represents the minority of patients with contralateral kidney metastasis reported in the literature.