A locally infiltrative juxtaglomerular cell tumor with unusual histologic features

Juxtaglomerular cell tumor (JGCT) is an exceptionally rare renal tumor with a predominantly benign clinical course and classically bland histology. It commonly presents in young adults and manifests as hypertension related to renin secretion. We report a JGCT initially thought to be a renal cell carcinoma. It was unique because of its size, high-grade histologic features and locally infiltrative nature–extension into the renal pelvis. It is unclear whether features such as tumor necrosis, pleomorphism and increased proliferative activity are predictive of metastatic potential and/or locally aggressive behavior. Clinical follow-up may be warranted in such cases.