Primary hyperparathyroidism due to parathyroid tumors: how the disease has changed. Analysis of results in 335 patients who underwent surgery during the last 20 years

Sporadic primary hyperparathyroidism is a relatively common disease and is the main cause of hypercalcemia in outpatients, with an incidence ranging between 5 and 20 cases per 100,000. The estimated prevalence of PHPT in women aged over 60 years-old may reach 4 per 1,000. In hypercalcemic patients, when serum PTH is elevated, the diagnosis of PHPT is easily made, especially if there are clinical manifestations. Hypercalcemic patients with high PTH serum levels are unlikely to be due to causes other than primary hyperparathyroidism. Occasionally, a normocalcemic primary hyperparathyroidism can also occur in patients with low serum protein, renal failure, increased dietary phosphate intake or vitamin D deficiency. Currently, 80-90% of patients with confirmed primary hyperparathyroidism are asymptomatic, as the disease is commonly an incidental finding during routine hematologic screening or is discovered among postmenopausal women who undergo dual-energy X-ray absorptiometry for the diagnosis of possible bone alterations and risk of fracture.