Renal pseudomass: be aware of splenorenal fusion

Splenosis is the heterotopic implantation of splenic tissue that usually occurs in a previous major abdominal trauma or splenectomy setting. However, splenorenal fusion is an uncommon entity, categorised as a developmental anomaly. There have been several confirmed cases in the literature. Despite some helpful imaging features, it can be easily misdiagnosed as a neoplastic renal mass, resulting in unnecessary nephrectomy. Here we presented a case of splenorenal fusion in an elderly female patient, which was initially misdiagnosed as renal cell carcinoma in sonography. More specific imaging modalities and biopsy are helpful in suggesting the correct diagnosis.