Maxillary Brown Tumor as a Rare Complication of Hyperparathyroidism

Secondary hyperparathyroidism is a common complication of end stage renal disease (ESRD). The inherent impaired phosphorus and calcium metabolism result in altered bone metabolism, which rarely may manifest as osteitis fibrosa cystica with approximately 2% presenting as brown tumors. Brown tumors are areas of excessive bone resorption replaced by giant cells and fibrovascular tissue. Maxillofacial brown tumors are rare and result in increased patient morbidity due to associated nasal bleeding, diffuse pain and focal deformities. Nonetheless, these tumors are treatable and may regress following reduced parathyroid hormone (PTH) levels. Case of a 64-years-old Hispanic male with history of ESRD on hemodialysis for more than 20 years, secondary hyperparathyroidism with fragility fractures of femur status post parathyroidectomy on years 1999 and 2010, coronary artery disease and hypertension, who was consulted to our service for evaluation of a bleeding nasal septum mass suspected of a brown tumor. The patient presented to the emergency room with a massive spontaneous nasal bleeding which was subsequently controlled and evaluated by imaging. Maxillofacial CT scan without contrast showed an expansile soft tissue mass at the right maxillary sinus measuring 3.4 x 3.5 x 3.7 cm with innumerable, similar lesions distributed throughout the cranial, cervical and visualized portions of the shoulder girdle bones. Biochemical evaluation was remarkable for PTH levels 1,229 pg/ml (nl, 18.5 – 88.0 pg/ml), corrected serum calcium 9.0 mg/dl (nl, 8.3 – 10.6 mg/dl), alkaline phosphate levels 391 U/L (nl, 46 – 116 U/L), serum phosphoros 5.5 mg/dl (nl, 2.5 – 4.5 mg/dl), calciferol levels 32.2 ng/ml (nl, 30 – 100 ng/ml) and an estimated glomerular filtration rate at 21 ml/min/1.73 m(2) (nl, > 60 ml/min/1.73 m(2)). An excisional tissue biopsy showed osteoclastic-like multinucleated cells consistent with a brown tumor. These findings are consistent with secondary hyperparathyroidism complicated with osteitis fibrosa cystica. Following histologic diagnosis, a (99m)Tc-Sestamibi parathyroid scan showed two focal lesions of increased radiotracer uptake in the lower poles of the thyroid confirming parathyroid hyperplasia. Patient’s medical therapy was optimized by increasing cinacalcet dose and adding calcitriol, while continuing Sevelamer. Serum calcium, PTH, and phosphorous levels were closely monitored. Finally, patient was referred for parathyroidectomy. Patients with ESRD are at high risk of developing secondary hyperparathyroidism. Even with prior parathyroidectomy, these patients can develop disease recurrence. Early recognition and management of secondary hyperparathyroidism is crucial to decrease disease complications such as Brown tumors.