Zhang Hao, Wroblewski Kristen, Jiang Yulei, Penney Bill C, Appelbaum Daniel, Simon Cassie A, Salgia Ravi, Pu Yonglin
Department of Radiology, The University of Chicago, Chicago, IL 60637, United States; Department of Radiology, First Hospital of Lanzhou University, Lanzhou, Gansu 730000, China.
Department of Public Health Sciences, The University of Chicago, Chicago, IL 60637, United States.
Lung Cancer. 2015 Jul;89(1):43-9. doi: 10.1016/j.lungcan.2015.03.023. Epub 2015 Apr 9.
Whole-body metabolic tumor volume (MTVWB) has been shown of prognostic value for non-small cell lung cancer (NSCLC) beyond that of TNM stage, age, gender, performance status, and treatment selection. The current TNM staging system does not incorporate tumor volumetric information. We propose a new PET/CT volumetric prognostic (PVP) index that combines the prognostic value of MTVWB and TNM stage.
Based on 328 consecutive NSCLC patients with a baseline PET/CT scan before treatment, from which MTVWB was measured semi-automatically, we estimated hazard ratios (HRs) for ln(MTVWB) and TNM stage from a Cox proportional hazard regression model that consisted of only ln(MTVWB) and TNM stage as prognostic variables of overall survival. We used the regression coefficients, which gave rise to the HRs, as weights to formulate the PET/CT volumetric prognostic (PVP) index. We also compared the prognostic value of the PVP index against that of TNM stage alone and ln(MTVWB) alone with univariate and multivariate survival analyses and C-statistics.
Univariate analysis C-statistic for the PVP index (C=0.71) was statistically significantly greater than those for TNM stage alone (C=0.67, p<0.01) and for ln(MTVWB) alone (C=0.69, p=0.033). Multivariate analyses showed that the PVP index yielded significantly greater discriminatory power (C=0.74) than similar models based on either TNM stage (C=0.72, p<0.01) or ln(MTVWB) (C=0.73, p<0.01). Lower values of the PVP index were associated with significantly better overall survival (adjusted HR=2.70, 95%CI [2.16, 3.37]).
The PVP index provides a practical means for clinicians to combine the prognostic value of MTVWB and TNM stage and offers significantly better prognostic accuracy for overall survival of NSCLC patients than the current TNM staging system or metabolic tumor burden alone.
全身代谢肿瘤体积（MTVWB）已显示出对非小细胞肺癌（NSCLC）具有预后价值，其预后价值超出了TNM分期、年龄、性别、体能状态和治疗选择等因素。当前的TNM分期系统未纳入肿瘤体积信息。我们提出了一种新的PET/CT体积预后（PVP）指数，该指数结合了MTVWB和TNM分期的预后价值。
基于328例连续的NSCLC患者，这些患者在治疗前进行了基线PET/CT扫描，并半自动测量了MTVWB。我们从Cox比例风险回归模型中估计ln(MTVWB)和TNM分期的风险比（HRs），该模型仅将ln(MTVWB)和TNM分期作为总生存的预后变量。我们使用产生HRs的回归系数作为权重来制定PET/CT体积预后（PVP）指数。我们还通过单变量和多变量生存分析以及C统计量，比较了PVP指数与单独的TNM分期和单独的ln(MTVWB)的预后价值。
PVP指数的单变量分析C统计量（C = 0.71）在统计学上显著高于单独的TNM分期（C = 0.67，p < 0.01）和单独的ln(MTVWB)（C = 0.69，p = 0.033）。多变量分析表明，PVP指数产生的鉴别力（C = 0.74）明显高于基于TNM分期（C = 0.72，p < 0.01）或ln(MTVWB)（C = 0.73，p < 0.01）的类似模型。PVP指数值越低，总生存情况越好（调整后的HR = 2.70，95%CI [2.16, 3.37]）。
PVP指数为临床医生提供了一种结合MTVWB和TNM分期预后价值的实用方法，并且对于NSCLC患者的总生存，其预后准确性明显优于当前的TNM分期系统或单独的代谢肿瘤负荷。
