Parathyroid carcinoma: lessons from a rare malignancy of head and neck—a case series

Parathyroid carcinoma (PC) is a very rare head-neck malignancy. Because the symptoms of parathyroid carcinoma are similar to those of benign causes of hyperparathyroidism, it may be not easy to detect it before surgery. The management of PC after initial surgery will be perplexing because of the adequacy of surgery. We wish to describe the difficulties encountered throughout treatment using a literature review. We conducted a retrospective analysis of individuals with parathyroid carcinoma who had treatment at our department between 2017 and 2022. We gathered data on the clinical profile, investigations, management of hypercalcemia, surgical techniques, histopathological features, adjuvant therapy, and outcomes. We treated three patients with parathyroid carcinoma: Two patients with inferior parathyroid carcinoma and one with superior parathyroid carcinoma. Generalized weakness and bony pain are the predominant symptoms. In all cases, the tumor was located using 99Tc MIBI / SPECT scintigraphy and Ultrasonography. Hemithyroidectomy and tumor excision were done as the surgery of choice. All are disease-free at the 12th-month follow-up. We suggested that parathyroid hormone testing be performed in all bony fibrous lesions to rule out hyperparathyroidism. PC is a likely diagnosis when there is noticeable throat swelling, elevated PTH levels greater than 400 IU/L, and serum calcium levels greater than 15 mg/dL.