Parathyroid carcinoma: a case series.

Introduction: We present 3 patients with parathyroid carcinoma and describe their presentations, clinical profiles, and management. Materials and Methods: A case series review of medical records. Results: Two women and 1 man (age range, 32 to 57 years) had parathyroid cancer and primary hyperparathyroidism (PHPT). One patient presented with osteitis fibrosa, 1 with renal stone and a neck mass, and 1 with recurrence of PHPT after excision of supposedly benign parathyroid adenoma 4 years ago. All had severe hypercalcaemia and elevated parathyroid hormone levels that ranged from 4 to 43 times above the normal range. Exploration of the neck clearly identified 1 parathyroid tumour with local invasion; 2 other specimens showed capsular and vascular invasion on frozen section and final histology. All 3 patients underwent parathyroidectomy and ipsilateral hemithyroidectomy. Parathyroid size ranged from 1.3 to 4 cm and no lymph node metastasis was identified. No patient had tumour recurrence after a follow-up period of 1 year. Conclusion: Parathyroid carcinoma is a rare endocrine malignancy. Suspicious features include marked hypercalcaemia, neck mass, and local recurrence. Parathyroidectomy with ipsilateral hemithyroidectomy and nodal clearance gives the best chance of reducing local tumour recurrence. Ann Acad Med Singapore 2005;34:443-6