Rounds 8
Correct Diagnosis: Brown Tumor (osteoclastoma) associated with secondary hyperparathyroidism
Discussion:
Brown Tumors, or osteoclastomas, are rarely seen complications of longstanding hyperparathyroidism (HPT). They occur most commonly in primary HPT, but can also be seen as a consequence of untreated renal osteodystrophy. These lesions are benign, and represent localized accumulations of osteoclasts, fibrous tissue, and blood; their high hemosiderin content gives them their characteristic brown color. They occur as single or multiple lesions, and can be found both within bone and in the adjacent soft tissues. When left untreated, they can undergo central necrosis and cyst formation. Other radiographic manifestations of HPT, including subperiosteal, subchondral, and subligamentous bone resorption (especially of the middle phalanges of the hand), are often seen in association with these lesions. Because they are benign, they must be distinguished from metastatic carcinoma and multiple myeloma in the right clinical setting. Treatment of secondary HPT includes aggressive hemodialysis, judicious use of phosphate binders and calcitriol, and if necessary, parathyroidectomy.
References:
- Pecovnik Balon B, Kavalar R. Brown tumor in association with secondary hyperparathyroidism. A case report and review of the literature. Am J Nephrol 18(5):460-3, 1998.
- Gupta A, Horattas MC, Moattari AR, Shorten SD. Disseminated brown tumors from hyperparathyroidism masquerading as metastatic cancer: a complication of parathyroid carcinoma. Am Surg 67(10):951-5, 2001.
- Agarwal G, Mishra SK, Kar DK, Singh AK, Arya V, Gupta SK, Mithal A. Recovery pattern of patients with osteitis fibrosa cystica in primary hyperparathyroidism after successful parathyroidectomy. Surgery 132(6):1075-83, 2002.
ACR 2007 Highlights
Pathophysiology 2007