Juxtaglomerular Cell Tumor

Juxtaglomerular cell tumor is a benign renal tumor that arises from the specialized smooth muscle cells in the afferent arteriole of the juxtaglomerular apparatus. Juxtaglomerular apparatus normally plays a role in regulating blood pressure via renin release. The tumor usually presents in young adults (mean age 27 years) with a slight female predominance. Most cases show elevated renin production resulting in hypertension that is corrected surgically with the removal of the tumor. Other symptoms include headaches, polyuria, nocturia, dizziness, and vomiting. Some tumors are non-functioning. Most cases are unilateral, solitary, small (usually less than 3 cm) and located in the cortex. The tumor cells are monomorphic and may be arranged in sheets (shown here), anastomosing cords, or trabecular structures. There is well-developed vasculature consisting of small venules, muscular arterioles, and capillaries interposed between tumor cells.