Ectopic parathyroid adenoma presenting as facial expansile growths

Ectopic parathyroid adenoma presenting as facial expansile growths. Background: Giant cell reparative granuloma of the facial skeleton is a rare presentation of hyperparathyroidism. Methodology: A 17-year-old girl presented with progressive expansile bony growths of the mandible and maxilla. The case was investigated using biopsies, blood tests, imaging, and surgery. Results: Biopsies confirmed giant cell reparative granuloma. Blood testing revealed very high parathyroid hormone levels, and brown tumours due to primary hyperparathyroidism weresuspected. Surgical removal of an ectopic adenoma led to correction of the endocrine condition. Conclusions: To our knowledge, this is the first reported case of multiple brown tumours of the facial skeleton due to an ectopic parathyroid adenoma. Diagnostic pitfalls and therapeutic challenges are described.