Brown Tumour


A hyperparathyroidism-induced tumour-like mass of bony tissue characterised by fibrosis, cyst formation, marked osteoclastic resorption, multinucleated giant cells, and hemosiderin—which imparts the brown color deposits and rounded, cyst-like radiologic defects; brown tumours also occur in 2º hyperparathyroidism and may be the first sign of renal osteodystrophy in patients with ESRD who are kept alive by renal dialysis, and have enough time to develop the osseous reaction