Parathyroid Carcinoma: Outcome Analysis of 16 Cases from a Single Center

Purpose: Parathyroid carcinoma is an extremely rare malignancy, but there is still a lack of understanding of the natural course and prognostic implications of this disease. In this study, we reviewed the clinicopathological characteristics of patients with parathyroid carcinoma treated at our institution. Methods: Patients with parathyroid carcinoma were included in this study. We reviewed the clinicopathological characteristics of patients with parathyroid carcinoma treated at our institution, and evaluated patient outcomes and prognostic factors. Results: A total of 16 patients with parathyroid carcinoma were included in this study. The median follow-up duration was 61.5 months (range, 7–215 months), and seven patients developed recurrence (7/16, 43.8%). Four patients had died from parathyroid carcinoma (4/16, 25.0%) at the time of the analysis. Increased serum intact parathyroid hormone (iPTH) level during follow-up was an independent risk factor for recurrence after making adjustments for multivariate analysis. Trends of increasing serum calcium and iPTH levels after surgery were associated with the development of recurrence. Conclusion: We observed a good survival rate after initial surgery for parathyroid carcinoma. However, the rate of recurrence was relatively high and early detection of recurrence is critical. Close monitoring during follow-up is necessary, and a serial check for serum calcium and iPTH level may prove useful. When steadily increasing serum calcium and iPTH results are observed, careful evaluation for recurrence is needed.