Postoperative local-regional radiation therapy in the treatment of parathyroid carcinoma: The MD Anderson experience of 35 years.

PURPOSE: We aimed to investigate outcomes of locoregional radiation therapy (XRT) in parathyroid carcinoma (PC) patients at a single institution over 35 years.

METHODS AND MATERIALS: Retrospective review of PC patients who received postoperative locoregional XRT (1980-2015). Patients were grouped according to XRT after PC initial operation or after salvage surgery. All patients with a histopathological diagnosis of PC who had postoperative locoregional XRT at our institution were included. All patients with a histopathological diagnosis of uncertain malignancy, suggestive for malignancy, or atypical parathyroid tumors and those who had XRT outside our institution were excluded.

RESULTS

Eight patients received XRT, 4 in each group, with a median follow-up of 12.5 years. The 4 patients who had XRT after initial surgery all had an oncologic operation, including ipsilateral thyroid lobectomy and central neck dissection, and all of these patients were disease-free at last follow-up. Of the 4 patients who received XRT after salvage surgery, only 1 remained disease free. There were no major complications/long-term side effects associated with XRT.

CONCLUSIONS

XRT is well tolerated as postoperative locoregional treatment of patients with PC. Whether it is needed, and the timing of administering XRT, remains to be established.