Brown Tumors of Hyperparathyroidism: A 13-Year Retrospective Case Series from a Tertiary Center in South India.

Introduction: Brown tumors are rare, non-neoplastic osteolytic lesions resulting from hyperparathyroidism (HPT), often mimicking bone metastases. Although their incidence has declined in developed nations due to early biochemical screening, they remain clinically relevant in regions with prevalent Vitamin D deficiency. We present a 13-year retrospective analysis of brown tumor cases managed at a tertiary care center in South India. Material and Methods: Twelve patients diagnosed with brown tumors between 2012 and 2025 were retrospectively reviewed. Clinical presentation, biochemical findings, radiological features, anatomical distribution, management strategies, and outcomes were analyzed. All cases were histologically confirmed and correlated with HPT profiles. Results: The mean age was 43.3 years (range 25-63), with a female predominance (66.6%). Localized pain was the most common presentation (58.3%), followed by pathological fractures and soft-tissue swellings. Primary HPT accounted for 83.3% of cases, whereas 16.7% were secondary. Sixteen tumors were identified, most frequently affecting the femur and hand. Conservative management was adopted in 7 patients (58.3%), whereas 5 patients (41.7%) underwent surgical intervention, including fixation, curettage, and hemiarthroplasty. Eight patients underwent parathyroidectomy, predominantly for adenomas. Two patients died before surgery due to complications of hypercalcemia. Lesions regressed following parathyroidectomy in most cases, with a mean fracture healing time of 3 months. Conclusion: Brown tumors, though rare, should be considered in the differential diagnosis of lytic bone lesions in endemic regions. Biochemical testing and timely parathyroidectomy remain central to management. This case series, the first from South India, underscores the variability in presentation and highlights the importance of multidisciplinary care in optimizing outcomes.