UNASSIGNED: This study retrospectively enrolled 387 patients newly diagnosed with NPC between January 2010 and January 2013. A four-category MRI-LRG system based on the areal analysis of RT-induced fibrosis and residual tumor was established. Univariate analysis was performed using the Kaplan-Meier method, and comparisons were conducted via the log-rank test. Multivariate analyses were conducted using Cox regression models to calculate the hazard ratios (HRs) with 95% confidence intervals (CIs) and adjusted P values. Survival curves were calculated using the Kaplan-Meier method and compared using the log-rank test.
UNASSIGNED: The sum of MRI-LRG scores (LRG-sum) was an independent prognostic factor for progression-free survival (PFS) (HR 2.50, 95% CI: 1.28-4.90; P<0.001). LRG-sum ≤9 and >9 showed a poorer 5-year PFS rate than did LRG-sum ≤2 (66.1%, 42.9%, and 77.6%, respectively; P<0.001). A survival clustering analysis-based decision tree model showed more complex interactions among LRG-sum and pretreatment and post-RT Epstein-Barr virus (EBV) DNA, yielding four patient clusters with differentiated disease progression risks (5-year PFS rates of 89.5%, 76.4%, 57.6%, and 27.8%, respectively), which showed better risk stratification than did post-RT EBV DNA alone (P<0.001).
UNASSIGNED: The MRI-LRG system adds prognostic information and is a potentially reliable, noninvasive means to stratify treatment modalities for patients with NPC.
■本研究回顾性纳入了2010年1月至2013年1月间新诊断为NPC的387例患者。建立了基于RT诱导的纤维化和残留肿瘤面积分析的四类MRI-LRG系统。使用Kaplan-Meier方法进行单变量分析,并通过对数秩检验进行比较。使用Cox回归模型进行多变量分析,以95%置信区间(CI)和调整后的P值计算风险比(HR)。使用Kaplan-Meier方法计算存活曲线,并使用对数秩检验进行比较。
■MRI-LRG评分总和(LRG-sum)是无进展生存期(PFS)的独立预后因素(HR2.50,95%CI:1.28-4.90;P<0.001)。LRG-sum≤9和>9的5年PFS率低于LRG-sum≤2(66.1%,42.9%,77.6%,分别;P<0.001)。基于生存聚类分析的决策树模型显示了LRG-sum与预处理和RT后EB病毒(EBV)DNA之间更复杂的相互作用,产生四个具有不同疾病进展风险的患者群(5年PFS率为89.5%,76.4%,57.6%,27.8%,分别),与单纯RT后EBVDNA相比,显示出更好的风险分层(P<0.001)。
■MRI-LRG系统增加了预后信息,具有潜在的可靠性,对NPC患者的治疗方式进行分层的无创手段。