β£What is the pathophysiology of Brown's tumor?Low vitamin D activation due to renal damage β low calcium in blood β secondary hyperparathyroidism β excessive osteoclastic resorption β Osteotitis Fibrosa Cystica (brown tumor)Decreased renal excretion of phosphate β high phosphate levelsβ£What do they present with?Cystic lesions - commonly occur in mandible, maxilla but can also occur in other parts of the bodyβ£What investigations?PTH levelsβ£Management of brown's tumor?Treat underlying renal problemβ£How to tell secondary vs tertiary parathyroidism?