1 Department of Nuclear Medicine, 2 Department of Laboratory Medicine, 3 Department of Radiology, the First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China.
J Thorac Dis. 2014 Jun;6(6):677-83. doi: 10.3978/j.issn.2072-1439.2014.05.10.
(18)F-FDG PET/CT is increasingly used in evaluation of treatment response for patients with non-small cell lung cancer (NSCLC). There is a need for an accurate criterion to evaluate the effect and predict the prognosis. The aim of this study is to evaluate therapeutic response in NSCLC with comparing PET response criteria in solid tumors (PERCIST) to response evaluation criteria in solid tumors (RECIST) criteria on PET/CT.
Forty-four NSCLC patients who received chemotherapy but no surgery were studied. Chemotherapeutic responses were evaluated using (18)F-FDG PET and CT according to the RECIST and PERCIST methodologies. PET/CT scans were obtained before chemotherapy and after 2 or 4-6 cycles' chemotherapy. The percentage changes of tumor longest diameters and standardized uptake value (SUV) (corrected for lean body mass, SUL) before and after treatment were compared using paired t-test. The response was categorized into 4 levels according to RECIST and PERCIST: CR (CMR) =1, PR (PMR) =2, SD (SMD) =3, PD (PMD) =4. Pearson chi-square test was used to compare the proportion of four levels in RECIST and PERCIST. Finally the relationship between progression-free survival (PFS) and clinicopathologic parameters (such as TNM staging, percentage changes in diameters and SUL, RECIST and PERCIST results etc.) were evaluated using univariate and multivariate Cox proportional hazards regression method.
The difference of percentage changes between diameters and SUL was not significant using paired t-test (t=-1.69, P=0.098). However the difference was statistically significant in the 40 cases without increasing SUL (t=-3.31, P=0.002). The difference of evaluation results between RECIST and PERCIST was not significant by chi-square test (χ(2)=5.008, P=0.171). If RECIST evaluation excluded the new lesions which could not be found or identified on CT images the difference between RECIST and PERCIST was significant (χ(2)=11.759, P=0.007). Reduction rate of SULpeak (%), RECIST and PERCIST results were significant factors in univariate Cox analysis. But Multivariate Cox proportional hazards regression analysis demonstrated that only PERCIST was a significant factor for predicting DFS [hazard ratio (HR), 3.20; 95% (CI), 1.85-5.54; P<0.001].
PERCIST and RECIST criteria have good consistency and PERCIST (or PET) is more sensitive in detecting complete remission (CR) and progression. PERCIST might be the significant predictor of outcomes. The combination of PERCIST and RECIST would provide clinicians more accurate information of therapeutic response in earlier stage of treatment.
（18）F-FDG PET/CT 越来越多地用于评估非小细胞肺癌（NSCLC）患者的治疗反应。需要一种准确的标准来评估疗效并预测预后。本研究旨在通过比较实体瘤 PET 疗效评价标准（PERCIST）与实体瘤疗效评价标准（RECIST）在 PET/CT 上的疗效，评估 NSCLC 的治疗反应。
对 44 例接受化疗但未手术的 NSCLC 患者进行研究。根据 RECIST 和 PERCIST 方法，用（18）F-FDG PET 和 CT 评估化疗反应。在化疗前和化疗 2 或 4-6 个周期后进行 PET/CT 扫描。使用配对 t 检验比较治疗前后肿瘤最长直径和标准化摄取值（SUV）（按瘦体重校正，SUL）的百分比变化。根据 RECIST 和 PERCIST 将反应分为 4 个水平：CR（CMR）=1、PR（PMR）=2、SD（SMD）=3、PD（PMD）=4。使用 Pearson 卡方检验比较 RECIST 和 PERCIST 中四个水平的比例。最后，使用单变量和多变量 Cox 比例风险回归方法评估无进展生存期（PFS）与临床病理参数（如 TNM 分期、直径和 SUL 的百分比变化、RECIST 和 PERCIST 结果等）之间的关系。
配对 t 检验显示直径和 SUL 的百分比变化差异无统计学意义（t=-1.69，P=0.098）。然而，在 40 例未增加 SUL 的患者中，差异具有统计学意义（t=-3.31，P=0.002）。卡方检验显示 RECIST 和 PERCIST 的评估结果差异无统计学意义（χ（2）=5.008，P=0.171）。如果将 RECIST 评估排除 CT 图像上无法发现或识别的新病变，则 RECIST 和 PERCIST 之间的差异具有统计学意义（χ（2）=11.759，P=0.007）。SULpeak（%）、RECIST 和 PERCIST 结果的降低率是单因素 Cox 分析中的显著因素。但多因素 Cox 比例风险回归分析表明，只有 PERCIST 是预测 DFS 的显著因素[风险比（HR），3.20；95%（CI），1.85-5.54；P<0.001]。
PERCIST 和 RECIST 标准具有良好的一致性，PERCIST（或 PET）在检测完全缓解（CR）和进展方面更敏感。PERCIST 可能是预测结果的重要指标。PERCIST 和 RECIST 的结合可以为临床医生提供治疗早期更准确的治疗反应信息。
