Renal lymphoma. Atypical presentation of a renal tumor.

Primary renal lymphoma is a rare lesion that represents less than 1% of the kidney's lesions. The authors discuss the case of a 67-year-old woman with a renal mass identified 7 years after treatment of a non-Hodgkin's lymphoma, and analyze clinical and prognostic aspects of renal lymphomas. Radiological findings in this case showed an uncommon presentation of the renal lymphomatous lesion which served as a warning that tumors might appear during follow-up as atypical and uncommon lesions.