Mild primary hyperparathyroidism-to treat or not to treat?

INTRODUCTION: The presentation of primary hyperparathyroidism (PHPT) has shifted from a disease characterized by renal and skeletal complications to a mild or asymptomatic condition. Modern imaging allows localization of a surgical target in the majority of cases. SOURCES OF DATA: Data were collected from literature searches of online databases including PUBMED, MEDLINE and Cochrane. A narrative review was performed. AREAS OF AGREEMENT: Parathyroidectomy is the only therapy with curative potential with good outcomes and low risk of complications in experienced hands. Current guidelines advocate that surgery is offered in all symptomatic cases and in those who meet criteria depending on age, serum calcium concentration, skeletal and renal parameters. A structured monitoring approach should be offered to those who do not undergo surgery. AREAS OF CONTROVERSY: Thresholds for intervention to improve skeletal and renal outcomes are debatable. In addition, controversy persists over the benefit of surgery for non-skeletal/renal outcomes. GROWING POINTS: The role of medical management of PHPT using agents such as bisphosphonates, denosumab and cinacalcet are discussed. AREAS TIMELY FOR DEVELOPING RESEARCH: In summary, further data on the natural history and effects of treatment of mild and asymptomatic PHPT are required to determine thresholds for surgery. In particular, further investigations of non-skeletal and non-renal parameters, such as neurocognitive quality of life and cardiovascular disease are required. Data on normocalcaemic PHPT are lacking. Large-scale randomized controlled trials would be welcome in these areas, however in view of the cost implications a more pragmatic approach may be to develop collaborative multi-centre registries.