Primary hyperparathyroidism associated with a giant cell tumor: One case in the distal radius.

Hyperparathyroidism can present itself as brown tumors (or osteolytic expansive lesions) that usually disappear after normalization of calcium and phosphate levels. It rarely occurs simultaneously with a giant cell tumor. The authors report one case of a localized form at the distal radius in a patient being followed for primary hyperparathyroidism. The diagnostic challenges related to the clinical and radiological similarities of these two pathological entities are discussed, as they can lead to delays in therapeutic management.