7073 Treasure or Terror: Dilemmas in the Management of a Giant Parathyroid Adenoma

Abstract Disclosure: A.D. Galia: None. R. De Guzman: None. S. Suib - Salvilla: None. Background: Primary hyperparathyroidism is a common endocrine disorder with an incidence of 25 per 100,000 people in the general population. More commonly caused by parathyroid adenomas in 80-85%, giant parathyroid adenomas weighing more than 3.5 g or measuring more than 2 cm may rarely occur. There have been no reported prevalence data of parathyroid adenoma among ASEAN countries, especially in the Philippines. Clinical Case: A 43-year-old, female, Filipino, initially asymptomatic with anterior neck mass for 8 years then presented with generalized body malaise, easy fatigability, lower extremities pain and numbness. Six years ago, neck ultrasound showed left thyroid nodule; abdominal sonogram showed bilateral medullary nephrocalcinosis, with hypercalcemia, elevated intact PTH, and elevated creatinine. She was unable to undergo further workup and management until she presented a few months ago because of generalized body malaise, abdominal pain, nausea, and vomiting because of hypercalcemia and non-oliguric renal failure. Serum ionized calcium was 1.90 mmol/L (NV 1.15 - 1.30), intact PTH 2000 pg/mL, and serum creatinine 6.08 mg/dL. With unavailability of calcitonin and pamidronate, medical management of hypercalcemia included cautious hydration followed by diuresis, zoledronic acid, and cinacalcet. Sestamibi scan showed a large parathyroid adenoma. Bone densitometry showed osteoporosis (T score = below -2.5). After medical evaluation, she underwent parathyroidectomy under general anesthesia. Intact PTH level perioperatively were as follows: pre-op = 2,078.2 pg/mL; 30 mins = 477.1 pg/mL; 1 hour = 335.7 pg/mL, 1 day = 67.2 pg/mL. The resected mass was 4.2 x 2.4 x 1.6 cm and weighed 4 g; histopathology report was consistent with Parathyroid Adenoma. Post-operatively, patient did not develop hungry bone syndrome. Conclusion: Giant parathyroid adenoma is a rare condition that is usually asymptomatic but can lead to serious complications. In the Philippines, limited availability of laboratory techniques (PTH and sestamibi scan) and availability of medications for hypercalcemia may contribute to underdiagnosis and management. Early detection and treatment can help prevent further complications and improve the overall quality of life. Presentation: 6/3/2024