Huge juxtacortical brown tumor in two patients with secondary hyper-parathyroidism due to chronic renal failure.

The brown tumor of the skeletal system is mainly caused by hyperparathyroidism (HPT), and HPT is divided into three categories according to its causes: primary, secondary and tertiary HPT. The secondary HPT patients with brown tumor caused by chronic renal insufficiency are rarely reported. The tumor occurs mostly in the bones such as metacarpals, phalanges, skull, pelvis, clavicle, ribs, femur and spine. We reported two cases of juxtacortical brown tumor in patients with HPT secondary to chronic renal insufficiency which has never been reported previously.