Surgical Management of Multiglandular Parathyroid Disease

Abstract There has been a paradigm shift in the approach to primary hyperparathyroidism (PHPT), from bilateral cervical exploration (BCE) to focused parathyroidectomy facilitated by preoperative localization scans. This has resulted in fewer four-gland explorations. Conversely, patients with negative localization are more likely to have smaller parathyroid tumors and, more often, have multiple gland disease (MGD). The diagnosis of mild or normocalcemic PHPT means that such patients now account for one-fifth of patients referred with PHPT. Nonlocalized disease may be associated with a 13% negative exploration rate and a surgical failure rate that is as high as 18%. Parathyroidectomy for MGD is, therefore, complex and associated with a higher operative failure compared with single-gland disease. Surgery in this setting poses several challenges; the diagnosis is often not clear until well into the neck exploration, as preoperative localization is rarely helpful. Furthermore, hyperplastic glands are typically much smaller than solitary parathyroid adenomas; therefore they are more difficult to identify. At times, it can be difficult to distinguish a small hyperplastic gland from a normal parathyroid. Finally, subtotal resection with or without thymectomy requires more surgical experience and judgment compared with excision of a solitary adenoma. For these reasons, consideration should be given toward centralizing the management both of patients predicted to have MGD, and those with negative preoperative localization, to high-volume centers. This chapter focuses on the pathology and etiology of sporadic multiglandular parathyroid disease and the rationale for the different surgical approaches used in the management of this challenging condition.