Reduced-dose Radiotherapy With/Without Concurrent Chemotherapy Versus Standard Chemoradiotherapy for High-risk Locoregionally Advanced Nasopharyngeal Carcinoma Who Achieved Complete Response After Induction Chemotherapy Plus Immunotherapy: a Randomized, Open-label, Multicenter, Phase III Trial
This prospective trial aims to enroll patients with high-risk stage III-IVA (AJCC 8th, except T3N0) locoregionally-advanced nasopharyngeal carcinoma (LANPC). Under the condition of full course of PD-1/PD-L1 blockades, patients who achieved both radiological and biological complete response after 3 cycles of platinum-based chemotherapy plus PD-1/PD-L1 blockades will be randomized in a 1:1:1 ratio to receive reduced-dose radiotherapy (60Gy/30F) alone or reduced-dose radiotherapy plus concurrent chemotherapy or standard dose radiotherapy (70Gy/33F) with concurrent chemotherapy. To solve the urgent problem of whether patients with high-risk advanced nasopharyngeal carcinoma are suitable for downgrade treatment.
• Histologically confirmed non-keratinizing nasopharyngeal carcinoma (differentiated or undifferentiated type, i.e., WHO type II or type III).
• Tumor staged as III-IVA (AJCC 8th, except T3N0).
• Patients who achieved both radiological and biological CR according to the RECIST criteria on the basis of MRI, PET-CT and endoscopic biopsy, and EBV DNA load =0 copies/mL (or lower than the test line) after 3 cycles of induction therapy of platinum-based chemotherapy plus immunotherapy.
• Eastern Cooperative Oncology Group performance status ≤1.
• Adequate organ function:
• Adequate marrow function: neutrocyte count≥4×10e9/L, hemoglobin ≥90g/L and platelet count ≥100×10e9/L.
• Adequate liver and kidney function: Alanine Aminotransferase (ALT)/Aspartate Aminotransferase (AST) ≤2.5×upper limit of normal (ULN), and bilirubin ≤ 2.5×ULN.; creatinine clearance rate ≥ 60 ml/min or creatinine of no more than 1.5 times the upper normal limit.
• Patients must be informed of the investigational nature of this study and give written informed consent.