本研究旨在评估辅助化疗（AC）对不同中点放疗（mid-RT）EB病毒（EBV）血浆DNA载量的局部晚期鼻咽癌（NPC）患者的疗效，并为决策提供依据。共有 675 名连续诊断为 III-IVa 期 NPC 的患者纳入本研究。所有患者均接受同步放化疗 (CCRT)，联合或不联合诱导化疗或 AC，或两者相结合。本研究的主要终点是无进展生存期 (PFS)。在 675 名入组患者中，248 名 (36.7%) 患者接受了 AC 治疗，427 名 (63.3%) 患者仅在 CCRT 后观察。总共有 149 名患者 (22.1%) 的中期 RT EBV DNA 水平可检测到，而 526 名患者 (77.9%) 的中期 RT EBV DNA 水平无法检测到。与中期 RT EBV DNA 检测不到的患者相比，RT 中期 EBV DNA 可检测到的患者的 5 年 PFS 较差（74.8% vs. 81.9%，P = 0.045）。 AC 组的 5 年 PFS 显着优于在 RT 中期检测到 EBV DNA 的患者中观察的患者（82.8% vs. 66.8%；HR，0.480；95% CI 0.250-0.919，P = 0.027）。多变量分析表明，治疗方法（AC 与观察）是 PFS 的独立预后因素（HR，0.37；95% CI 0.19-0.74，P = 0.005）。然而，在 RT 中期 EBV DNA 检测不到的患者中（5 年 PFS：HR 0.873，95% CI 0.565-1.349，P = 0.52），AC 组没有显示出观察到的生存获益。相比之下，AC 组可以降低疾病进展的风险观察可检测中期 RT EBV DNA 的患者。我们的研究结果表明，AC 对于治疗失败高风险的患者有效。版权所有 © 2024 Elsevier Ltd。保留所有权利。

This study aimed to evaluate the efficacy of adjuvant chemotherapy (AC) in patients with different midpoint-radiotherapy (mid-RT) Epstein-Barr virus (EBV) DNA plasma loads for locoregionally advanced nasopharyngeal carcinoma (NPC), and to provide decision-making regarding the use of AC.A total of 675 consecutive patients diagnosed with stage III-IVa NPC were enrolled in this study. All patients underwent concurrent chemoradiotherapy (CCRT), either with or without induction chemotherapy or AC, or a combination of both. The primary endpoint of this study was progression-free survival (PFS).Among the 675 enrolled patients, 248 (36.7 %) received AC and 427 (63.3 %) were only observed after CCRT. In total, 149 (22.1 %) patients had detectable mid-RT EBV DNA levels, whereas 526 (77.9 %) had undetectable mid-RT EBV DNA levels. Patients with detectable mid-RT EBV DNA had worse 5-year PFS than those with undetectable mid-RT EBV DNA (74.8 % vs. 81.9 %, P = 0.045). AC group showed significantly better 5-year PFS than observation in patients with detectable mid-RT EBV DNA (82.8 % vs. 66.8 %; HR, 0.480; 95 % CI 0.250-0.919, P = 0.027). Multivariate analyses demonstrated that the treatment methods (AC vs. observation) were independent prognostic factors for PFS (HR, 0.37; 95 % CI 0.19-0.74, P = 0.005). However, in patients with undetectable mid-RT EBV DNA (5-year PFS: HR 0.873, 95 % CI 0.565-1.349, P = 0.52), AC group showed no survival benefit for observation.AC could reduce the risk of disease progression compared to observation in patients with detectable mid-RT EBV DNA. Our findings suggest that AC is effective in patients at a high risk of treatment failure.Copyright © 2024 Elsevier Ltd. All rights reserved.