Suspicion Of Brown Tumor In A Young Woman Undergoing Maintenance Hemodialysis In A Rural Area: A Rare Case Report

Abstract

Brown tumor is a focal bone lesion caused by increased osteoclastic activity secondary to uncontrolled hyperparathyroidism. Although commonly associated with primary hyperparathyroidism, it rarely occurs in secondary hyperparathyroidism (SHPT) among young patients undergoing long-term hemodialysis. We report a rare and diagnostically challenging case of a 28-year-old woman on maintenance hemodialysis for seven years who presented with dyspnea, productive cough, and a progressively enlarging painless palatal mass causing difficulty in mastication, accompanied by a significant height loss of 13 cm. Laboratory investigations revealed markedly elevated intact parathyroid hormone (iPTH) levels (3,239 pg/mL), increased alkaline phosphatase (1,721 U/L), hypocalcemia (8.4 mg/dL), and vitamin D deficiency (14.4 ng/mL). Panoramic radiography demonstrated a multilocular lytic lesion with expansive involvement of the right maxilla, while fine-needle aspiration biopsy suggested a vascular lesion with abundant erythrocytes. Based on integrated clinical, biochemical, and radiological findings, the patient was diagnosed with suspected brown tumor secondary to SHPT. Maxillofacial involvement in brown tumors is rare and may mimic other giant cell lesions radiologically and histologically, making diagnosis challenging; however, markedly elevated iPTH levels strongly support the diagnosis. This case highlights the importance of a multimodal diagnostic approach and early monitoring of mineral and bone metabolism in long-term hemodialysis patients to improve outcomes.