Diagnostic challenge of the brown tumors in developing country: A case series

Brown tumors are non-neoplastic reactive tissue with osteoclasts multinucleated giant cells, and vascular and proliferative fibrous tissue. Hemorrhage results in significant bone resorption caused by hyperparathyroidism. This study provides information about the diagnosis challenge for brown tumor cases.

We report four cases that experience pathological fractures with moderate pain, multiple lytic lesions, severe hypercalcemia, increased ALP (Alkaline Phosphatase), and PTH (Parathyroid Hormone). Abnormal parathyroid mass was found in ultrasound. A bone scan described increasing radio uptake in various bones, a whole body scan, or parathyroid scintigraphy with ^99mTc-MIBI. Eventually, in all cases, the diagnosis of the brown tumor was confirmed through histopathological examination, which showed multiple nucleated giant cells with a deposit of hemosiderin pathognomonic for the brown tumor, and the diagnosis of primary hyperparathyroidism (PHPT) was confirmed in all cases.

These cases show that initial misdiagnosis of brown tumors as other bone tumors. A definitive diagnosis of brown tumors requires more than just histological confirmation. A comprehensive evaluation encompassing laboratory tests, imaging studies, clinical symptoms, and a multidisciplinary orthopedic-oncology board discussion is essential. Observations show that treating hyperparathyroidism alleviates the osteolytic lesions caused by brown tumors, despite the lack of clinical guidelines.

Based on a review of the literature and our clinical experience, we recommend screening serum calcium, phosphorus, and PTH levels in patients presenting with multiple lesions and widespread bone pain. This screening aims to rule out multiple bone lesions caused by PHPT.