Approximately 40% to 60% of patients experience a postsurgical recurrence, typically between 2 to 5 years after the initial resection.[1,2] Because it is difficult to establish a histologic diagnosis of parathyroid cancer at the time of initial surgery, the appearance of recurrent or metastatic tumor can be the first sign of malignancy.
Because these tumors are slow-growing, repeated resection of local recurrences and/or distant metastases can result in significant palliation.[4,5,6,7,8] Pulmonary metastases as well as bone metastases should be resected, if possible, to decrease the magnitude of the hypercalcemia.[7,9] Occasionally, long-term salvage is achieved in this group of patients with aggressive surgical treatment. The major morbidity of recurrent or metastatic parathyroid cancer results from severe hypercalcemia, which can be difficult to control. For patients not fit for surgery, treatment with bisphosphonates, plicamycin, calcitonin, and gallium pamidronate may control hypercalcemia. Control of malignant hypercalcemia with these medical measures is often only temporary. (Refer to the PDQ summary on Hypercalcemia for more information.)
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Surgical removal of the local recurrence with surgical removal of metastases when possible. Because parathyroid carcinoma can be slow-growing, resection of local recurrences or distant metastases can bring effective palliation but can rarely cure. Debulking of functional carcinomas may help reduce parathormone production.
Chemotherapy. Anecdotal reports show that short-term remissions with chemotherapy are possible.[10,11]
Current Clinical Trials
Check for U.S. clinical trials from NCI's list of cancer clinical trials that are now accepting patients with recurrent parathyroid cancer. The list of clinical trials can be further narrowed by location, drug, intervention, and other criteria.
General information about clinical trials is also available from the NCI Web site.
Anderson BJ, Samaan NA, Vassilopoulou-Sellin R, et al.: Parathyroid carcinoma: features and difficulties in diagnosis and management. Surgery 94 (6): 906-15, 1983.
Sandelin K, Auer G, Bondeson L, et al.: Prognostic factors in parathyroid cancer: a review of 95 cases. World J Surg 16 (4): 724-31, 1992 Jul-Aug.
Busaidy NL, Jimenez C, Habra MA, et al.: Parathyroid carcinoma: a 22-year experience. Head Neck 26 (8): 716-26, 2004.
Vetto JT, Brennan MF, Woodruf J, et al.: Parathyroid carcinoma: diagnosis and clinical history. Surgery 114 (5): 882-92, 1993.
Wynne AG, van Heerden J, Carney JA, et al.: Parathyroid carcinoma: clinical and pathologic features in 43 patients. Medicine (Baltimore) 71 (4): 197-205, 1992.
Hundahl SA, Fleming ID, Fremgen AM, et al.: Two hundred eighty-six cases of parathyroid carcinoma treated in the U.S. between 1985-1995: a National Cancer Data Base Report. The American College of Surgeons Commission on Cancer and the American Cancer Society. Cancer 86 (3): 538-44, 1999.
Obara T, Okamoto T, Ito Y, et al.: Surgical and medical management of patients with pulmonary metastasis from parathyroid carcinoma. Surgery 114 (6): 1040-8; discussion 1048-9, 1993.
Sandelin K: Parathyroid carcinoma. Cancer Treat Res 89: 183-92, 1997.
Flye MW, Brennan MF: Surgical resection of metastatic parathyroid carcinoma. Ann Surg 193 (4): 425-35, 1981.
Fraker DL: Parathyroid Tumors. In: DeVita VT Jr, Hellman S, Rosenberg SA, eds.: Cancer: Principles and Practice of Oncology. 7th ed. Philadelphia, Pa: Lippincott Williams & Wilkins, 2005, pp 1521-27.