Parathyroid carcinoma is a rare malignant endocrine disorder, occurs in 0.5 to 5% of cases of primary hyperparathyroidism. Complete healing can be achieved by appropiate radical surgical intervention. In early stages there are no marked clinical and cytological features, that could clearly distinguish malignant cases from benign forms before and during surgery.

526 patients had surgery for hyperparathyroidism, including 9 patients with parathyroid carcinoma between 2006-2022. 8 patients were male (age 27-74) and one female. The size of the tumor was between 14 and 55 mm. Preoperative calcium (2.95-4.51 mmol / l) and parathyroid hormone levels (28.2-349.5 pmol / l normal range: 1.6-6.9 pmol / l) were significantly elevated. Due to the suspicion of malignancy and the clinical picture, the enlarged parathyroid gland was removed with thyroid gland (lobectomy or total thyroidectomy). 30 minutes after removal intraoperative PTH level significantly decreased in 4 cases, 24-hour level in 9 cases

In one patient a recurrent laryngeal nerve paresis had occured. During follow-up, in 5 patients normal and in 1 case elevated PTH level was measured with normal calcium levels.

Initial radical surgical intervention is essential for complete healing of parathyroid carcinoma, since there is no other effective treatment modality. Therefore recognition of carcinoma, or suspicion of malignancy is important (eg considerably increased calcium, parathormone level, cystic, inhomogenous parathyroid hypertrophy greater than 3 cm). The success of surgery is suppurted by the measurement of intraoperative parathyroid hormone level. Continuous endocrine follow-up is needed to detect recurrence in time.