Recommendations after non-localizing sestamibi and ultrasound scans in primary hyperparathyroid disease: order more scans or explore surgically?

BACKGROUND: Treatment for primary hyperparathyroidism (PHPT) is surgical excision. Sestamibi and ultrasound scans, used to locate hyperfunctioning glands, can fail to do so. When both preoperative studies are non-localizing, options include 1) referral to a surgeon for a bilateral neck examination or 2) additional preoperative imaging.

STUDY DESIGN: Retrospective review of patients who underwent a parathyroidectomy from January 2010 to December 2011 at the University of Mississippi Medical Center (UMMC) was conducted. Only patients with negative or inconclusive findings on both sestamibi and ultrasound scans were included. The subsequent courses of action and the operative and postoperative outcomes were retrospectively reviewed.

RESULTS: Negative or inconclusive preoperative findings were present in 3 of 26 patients (12%). Additional imaging studies were ordered for 1 patient, which also produced nonlocalizing findings. All three patients underwent bilateral neck examination (BNE) with intraoperative PTH assay. A parathyroid adenoma was found in each case but was found in an ectopic location or in the presence of a multinodular goiter. Surgery yielded appropriate PTH levels for all 3 patients and each patient was eucalcemic at follow-up.

CONCLUSIONS: Non-localizing preoperative scans may result from ectopic parathyroid adenoma or presence of a multinodular goiter in PHPT. When presented with negative preoperative studies, we propose that the patient be scheduled for bilateral neck examination with intraoperative PTH assay rather than for additional preoperative studies. The surgeon's level of experience with four gland exploration and a thorough understanding of normal and aberrant positioning of parathyroid glands are imperative for patient safety and treatment, especially when localization studies have failed.