Giant Parathyroid Adenomas: A 28-Year Experience at a Tertiary Super-Specialty Hospital

Abstract

Background: Giant parathyroid adenomas represent a distinct clinical entity forming a subset under primary hyperparathyroidism (PHPT). They comprise lesions weighing more than 3.5 g. Our study aims to determine the clinical presentation, biochemical profile, outcomes, and pathological characterization of patients with giant parathyroid adenoma.

Materials and methods: Retrospective review of data of patients who underwent parathyroid surgery between January 1995 and December 2022 by a single surgeon. A total of 561 patients were identified, and out of these, 78 had glands measuring more than 3.5 g.

Results: The mean age was 42 years, and 51 (65%) were females. The most common complaint was bone pain (46%), followed by renal calculi (38%), with 15 (19%) patients presenting with hypercalcemic crisis. Median calcium value was 12.3 mg/dL, with median PTH, vitamin D, and ALP of 1025 pg/mL, 23 ng/mL, and 664 U/L, respectively. Fifty-three (68%) patients underwent focused parathyroidectomy, and 22 (28%) underwent neck exploration, with median postoperative calcium and PTH being 8.35 mg/dL and 37.8 pg/mL, respectively. The median weight was 7 g with a range from 3.58 g to a whopping 31 g. Symptomatic postoperative hypocalcemia was seen in 54 (69%), with 28 (36%) requiring intravenous calcium supplementation, and this was positively correlated with the preoperative ALP and PTH values.

Conclusion: Giant parathyroid adenomas present with florid symptoms with hypercalcemia and often hypercalcemic crisis. The biochemical workup, localization, and surgical management are similar to any other case of PHPT. Postoperatively these patients are prone to hypocalcemia, and the intravenous requirement of calcium can be predicted by preoperative ALP levels.

Keywords: giant parathyroid adenoma; hypercalcemic crisis; localization; primary hyperparathyroidism.