Beyond the Obvious: Unmasking Parathyroid Carcinoma in an Atypical Presentation
https://doi.org/10.15605/jafes.041.S1
- Author:
Pei Shin Lee
1
;
Poh Shean Wong
2
Author Information
1. Hospital Tuanku Ampuan Najihah
2. Hospital Tuanku Ja’afar
- Publication Type:Journal Article
- MeSH:
Parathyroid Neoplasms
- From:
Journal of the ASEAN Federation of Endocrine Societies
2026;41(S1):74-75
- CountryPhilippines
- Language:English
-
Abstract:
Introduction:Incidental hyperparathyroidism with hypercalcemia is
not uncommon. However, parathyroid carcinoma is an
extremely rare endocrine malignancy, accounting for less
than 1% of cases of primary hyperparathyroidism.
Case:A 57-year-old Malay female with well-controlled type 2
diabetes was incidentally found to have hypercalcemia
during hospitalization for pyelonephritis. She was
asymptomatic, with no history of calcium supplementation
or family history of endocrine disorders. Physical examination revealed no obvious neck swelling, and other
systemic examinations were unremarkable. Investigations
showed elevated serum calcium (2.87–3.4 mmol/L),
low phosphate (0.34–0.76 mmol/L), and elevated intact
parathyroid hormone (iPTH) (6.81 pmol/L). Her 25-OH
vitamin D was deficient (45.58 nmol/L). Ultrasound of the
neck revealed a solid lesion (1.6 × 2.0 × 2.8 cm) posterior
to the right thyroid lobe with bilateral thyroid nodules,
with the highest TR4, and normal cervical lymph nodes.
Sestamibi scan showed multinodular goiter with cold
nodules in bilateral thyroid lobes and a soft tissue lesion
posterior to the right thyroid lobe. Subsequently, she
underwent right hemithyroidectomy with intraoperative
nerve monitoring and right inferior parathyroidectomy
with intraoperative iPTH monitoring; the intraoperative
iPTH level dropped appropriately from 24 to 2.4 pmol/L.
Histopathological examination of the excised right parathyroid gland revealed parathyroid carcinoma, while the
right thyroid lobe showed nodular hyperplasia. Postoperatively, calcium and iPTH levels normalized, and she
remained well under follow-up.
Conclusion:Parathyroid carcinoma typically presents with markedly
elevated calcium and iPTH levels, often alongside a palpable
neck mass. However, in this patient, serum iPTH was only
slightly above the upper limit of normal, with tumor size
less than 3 cm, no lymph node or surrounding structures
involvement from pre-operative evaluation imaging. This
highlights the variability in both physical and biochemical
presentations of parathyroid carcinoma and the challenges
in distinguishing it from benign parathyroid tumors preoperatively.
- Full text:202608041057088568EP_A100.pdf
