[An historical case of malignant hyperparathyroidism with unusual metastatic sites].

We report a historical case of hyperparathyroidism in a young patient hospitalized for an array of osteolytic foci and incomplete fracture associated with a swollen neck, revealing a very special form of a metastatic parathyroid carcinoma with unusual multiple locations and exceptional medullary flooding. Carcinoma of the parathyroid gland produces a malignant hypersecreting tumor particularly difficult to diagnose. Treatment of this rare tumor is primarily surgical. The preoperative syndrome is unusually severe primary hyperparathyroidism. Intraoperatively, the size of the tumor and its local extension to surrounding tissue are highly suggestive. Confirmation requires pathological analysis of the operative specimens and can be further supported by the clinical course of local recurrence or metastasic spread. Specific immunohistochemical techniques have recently been shown to be contributive. The diagnosis is strengthened in the presence of associated Schantz and Castelman criteria. Foci of local extension can be identified preoperatively with ultrasound, (99m)Tc-sestamibi scintigraphy and MRI of the neck and mediastinum. The prognosis depends mainly on the possibility of achieving complete resection at the initial surgery. In some cases, very aggressive complementary postoperative radiotherapy is likely to improve locoregional control of the tumor. Chemotherapy alone or in combination with radiation has not demonstrated its effectiveness. The disease course and control can be monitored by regular assay of serum calcium and the parathormone.