Related Experiment Video
Updated: May 29, 2026
07:12
Establishment of a Simple and Effective Rat Model for Intraoperative Parathyroid Gland Imaging
Published on: August 17, 2022
Hyperparathyroidism due to eutopic PTH secretion from an ectopic intrathymic parathyroid cyst
Wai Han Hoi1, Melvin Khee-Shing Leow, Ashish Sule
1Department of Endocrinology, Tan Tock Seng Hospital, 11 Jalan Tan Tock Seng, Singapore. wai_han_hoi@ttsh.com.sg
Summary
A rare intrathymic parathyroid cyst caused hypercalcemia in a 56-year-old woman. Surgical removal of the cyst successfully normalized calcium levels, indicating resection as a curative treatment.
Area of Science:
- Endocrinology
- Surgical Pathology
Background:
- Parathyroid cysts are uncommon and infrequently associated with hyperparathyroidism.
- Intrathymic parathyroid tissue is a rare anatomical finding.
Observation:
- A 56-year-old woman presented with symptomatic hypercalcemia and an anterior mediastinal mass.
- Elevated serum calcium (15.6 mg/dL) and parathyroid hormone (PTH) levels (437 pg/mL) were noted.
Findings:
- Biopsy of the mediastinal mass revealed parathyroid tissue.
- Histological examination confirmed an intrathymic parathyroid cyst.
- Initial medical management (hydration, diuretics, bisphosphonates, calcitonin) temporarily reduced calcium levels.
Implications:
- This case highlights a rare cause of hypercalcemia and hyperparathyroidism.
- Surgical extirpation of intrathymic parathyroid cysts is a potentially curative treatment.
- The findings underscore the importance of considering ectopic parathyroid tissue in mediastinal masses.
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