Hill, Katherine A.1; Yip, Linwah2; Carty, Sally E.2; McCoy, Kelly L.2
1 Department of Surgery, University of Pittsburgh, Pittsburgh, PA, USA
2 Department of Surgery, Division of Endocrine Surgery, University of Pittsburgh, Pittsburgh, PA, USA
Background/Purpose: Compared to patients with sporadic primary hyperparathyroidism (SPHP), MEN-1 patients with primary hyperparathyroidism (MPHP) typically require more extensive dissection and have higher recurrence rates, but little is known about their risk of concurrent thyroid cancer (1,2).
1 Compare rates of concurrent thyroidectomy during parathyroid surgery among patients with MPHP vs SPHP
2 Compare rates of concurrent thyroid cancer in MPHP vs SPHP patients
Methods: MPHP and SPHP patients who had parathyroid operations from 1967-2014 were identified via prospectively collected database. We compared thyroid cancer-specific data of MPHP patients who had concurrent thyroidectomy to a 2:1 age and gender-matched cohort of SPHP patients who had simultaneous thyroidectomy. Clinically significant cancer was defined as >1cm (3). Statistical analysis was performed using student’s t test and Fisher’s exact test.
Results: As expected, MPHP patients had more lifetime parathyroid surgeries (mean 1.85 vs 1.02, p<0.01). Among 87 patients with MPHP, 29 (33%) required concomitant thyroidectomy vs 745/4031 (18%) with SPHP (p<0.01). In the matched cohort, 20 (34%) SPHP-associated thyroidectomies were not pre-operatively planned, vs 23 (79%) in the MPHP group (p<0.01). Among MPHP patients, histologic thyroid cancer was identified in 8/29 (28%) vs 27/58 (47%) SPHP patients (p=0.1). However, no MPHP patient had clinically significant cancer compared to 15/58 (26%) SPHP patients (p<0.01).
Discussion & Conclusion:
Patients with MPHP undergo more parathyroid operations and require unplanned concurrent thyroidectomy more frequently than SPHP patients. The incidence of small thyroid cancers is high (28%) in MPHP, however, clinically significant thyroid cancer is proportionally uncommon.
1. Yip L, Ogilvie JB, Challinor SM, Salata RA, Thull DL, Yim JH, Carty SE 2008 Identification of multiple endocrine neoplasia type 1 in patients with apparent sporadic primary hyperparathyroidism. Surgery 144:1002-1006; discussion 1006-1007.
2. Thakker RV, Newey PJ, Walls GV, Bilezikian J, Dralle H, Ebeling PR, Melmed S, Sakurai A, Tonelli F, Brandi ML, Endocrine S 2012 Clinical practice guidelines for multiple endocrine neoplasia type 1 (MEN1). J Clin Endocrinol Metab 97:2990-3011.
3. Haugen BR, Alexander EK, Bible KC, Doherty GM, Mandel SJ, Nikiforov YE, Pacini F, Randolph GW, Sawka AM, Schlumberger M, Schuff KG, Sherman SI, Sosa JA, Steward DL, Tuttle RM, Wartofsky L 2016 2015 American Thyroid Association Management Guidelines for Adult Patients with Thyroid Nodules and Differentiated Thyroid Cancer: The American Thyroid Association Guidelines Task Force on Thyroid Nodules and Differentiated Thyroid Cancer. Thyroid 26:1-133.