a brown tumor simulating bone metastases

Primary hyperparathyroidism usually presents with renal, gastrointestinal, mental and skeletal signs and symptoms. brown tumor is a benign lesion that arises as a direct result of parathyroid hormone on bone tissue in some patients with hyperparathyroidism. multiple brown tumors may simulate a malignant neoplasm and it is a real challenge for the clinicians in the differential diagnoses. here, we present a 68yearold man with multiple lytic lesions in pelvis bones, highly suspicious for metastatic malignancy that finally we found that the patient had primary hyperparathyroidism.