Intra-renal splenosis mimicking a solid renal mass

We present the case of a young woman found to have an exophytic solid renal mass who was referred to our institution for ablation of said mass versus partial nephrectomy. The patient had a history of splenectomy. Ultrasound demonstrated a homogeneous solid left renal mass, and the diagnosis of intra-renal splenosis was considered based on the patient's history. The diagnosis was confirmed using Tc-99 m heat-damaged red blood cell scintigraphy, obviating the need for an invasive procedure. The diagnosis of intra-renal splenosis should be considered for a solid renal mass with an appropriate history of prior splenic trauma or splenectomy.