Abandoning unilateral parathyroidectomy: why we reversed our position after 15,000 parathyroid operations.

BACKGROUND

Our group championed the techniques and benefits of unilateral parathyroidectomy. As our experience has matured, it seems this limited operation might be appropriate only occasionally.

METHODS

A single surgical group's experience with 15,000 parathyroidectomies examined the ongoing differences between unilateral and bilateral techniques for 10-year failure/recurrence, multigland removal, operative times, and length of stay.

RESULTS

With limited experience, 100% of operations were bilateral, decreasing to 32% by the 500(th) operation (p < 0.001), and long-term failure rates increased to 6%. Failures were 11 times more likely for unilateral explorations (p < 0.001 vs bilateral), causing gradual increases in bilateral explorations to 97% at the 14,000(th) operation (p < 0.001). Ten-year cure rates are unchanged for bilateral operations, and unilateral operations show continued slow recurrence rates of 5% (p < 0.001). Removal of more than one gland occurred 16 times more frequently when 4 glands were analyzed (p < 0.001), increasing cure rates to the current 99.4% (p < 0.001). Of 1,060 reoperations performed for failure at another institution, intraoperative parathyroid hormone levels fell >50% in 22% of patients, yet a second adenoma was subsequently found. Operative times decreased with experience; bilateral operations taking only 5.9 minutes longer on average (22.3 vs 16.4 minutes; p < 0.001), which is 25 minutes less than unilateral at the 500(th) operation (p < 0.001). By the 1,000(th) operation, incision size (2.5 ± 0.2 cm), anesthesia, and hospital stay (1.6 hours) were identical for unilateral and bilateral procedures.

CONCLUSIONS

Regardless of surgical adjuncts (scanning, intraoperative parathyroid hormone), unilateral parathyroidectomy will carry a 1-year failure rate of 3% to 5% and a 10-year recurrence rate of 4% to 6%. Allowing rapid analysis of all 4 glands through the same 1-inch incision has caused us to all but abandon unilateral parathyroidectomy.