Locoregional Radiotherapy in Metastatic Nasopharyngeal Cancer—Reply

In Reply We thank Thai et al and Sharma et al for their comments on our recent article.¹ We sincerely thank Dr Thai and colleagues for helping clarify the issue of chemotherapy followed by locoregional radiotherapy instead of concurrent chemoradiotherapy used in our study. In the current study, all patients received systemic chemotherapy followed by subsequent radiotherapy rather than chemotherapy plus concurrent radiotherapy.¹ In contrast, of the patients with metastatic nasopharyngeal carcinoma who received local radiotherapy in the US, 52% received concurrent chemotherapy plus radiotherapy, and only 40% received systemic chemotherapy plus subsequent radiotherapy.² Although no differences were observed between the upfront chemotherapy and subsequent radiotherapy strategy and the concurrent chemoradiation strategy in that analysis, the data regarding specific chemotherapy agents and cycle numbers were not available.² After considering the patients’ tolerance and ability to complete the 6 preplanned cycles of cisplatin plus fluorouracil and subsequent radical locoregional radiotherapy doses of 66 to 70 gray, we did not choose concurrent chemotherapy plus radiotherapy in this study.¹ Additionally, we have conducted a phase 2 prospective trial to evaluate the efficacy and safety of subsequent locoregional radiotherapy with concurrent programmed cell death protein 1 therapy in de novo metastatic nasopharyngeal carcinoma (ClinicalTrials.gov identifier: NCT04398056).