What is brown tumor?

➢ Symptomatic, untreated primary hyperparathyroidism manifests with three interrelated skeletal abnormalities: osteoporosis (generalized), brown tumors, and osteitis fibrosa cystica (generalized). ➢ Mass or nodular lesion of reactive reparative fibrous tissue with many Mp and multinucleated cells ➢ These lesions often undergo cystic degeneration. ➢ Generalized Osteitis Fibrosa Cystica: In case of severe HyperPTH; it includes: • Increased bone cell activity • Peritrabecular fibrosis, • Cystic brown tumors