化疗早期及中期18F-FDG PET/CT显像对56例弥漫大B细胞淋巴瘤患者预后的评估价值

The prognosis value of early and interim 18F-FDG-PET/CT scans in patients with diffuse large B-cell lymphoma

目的：探讨化疗早期及中期18F-FDG PET/CT显像判定弥漫大B细胞淋巴瘤（DLBCL）患者预后的价值，对比分析显像中残存病灶的判读标准。方法56例初治DLBCL患者接受R-CHOP/CHOP方案治疗，于化疗前、化疗早期（2周期，PET-2）及化疗中期（4周期，PET-4）行18F-FDG PET/CT扫描。使用五分法和最大标准摄取值减少率（%ΔSUVmax）法判读PET-2和PET-4。应用kappa检验评估五分法中3位阅片者判读结果的一致性，利用受试者操作特性（ROC）曲线计算%ΔSUVmax最佳阈值，构建%ΔSUVmax法、五分法的Kaplan-Meier生存曲线，使用Log-rank检验评估无进展生存（PFS）时间及整体生存（OS）时间。使用Cox回归模型进行预后相关因子多因素分析。结果全部56例DLBCL患者中男28例、女28例，中位年龄55（20～80）岁，中位随访时间24（6～42）个月。五分法（4分为界值）评估PET/CT图像，阅片者间一致性较好（κ＞0.600）。ROC曲线计算出PET-2、PET-4的%ΔSUVmax最佳界值分别为81%、74%。Kaplan-Meier生存分析结果显示，PET-2、PET-4均能预测56例DLBCL患者的预后， PET阴性患者的3年PFS和OS率明显高于PET阳性患者，差异有统计学意义（P＜0.05）。应用五分法判读PET-4，预测患者PFS准确性最高（76.79%）；66%ΔSUVmax法判读PET-2、PET-4预测OS准确性最好（76.79%、83.93%）。多因素分析结果显示，PET-2、PET-4均为优于国际预后指数评分的独立预后因子。结论 PET-2和PET-4均能预测DLBCL患者预后。PET-4预测患者预后更准确，其中使用66%ΔSUVmax法预测3年OS率、五分法预测3年PFS率更准确。

Objective To investigate the prognosis value of early and interim 18F-FDG-PET/CT scan in patients with diffuse large B-cell lymphoma （DLBCL） to establish the suitable criteria for evaluating posttherapeutic lesions in scans. Method Fifty-six newly diagnosed DLBCL patients were enrolled in the study, and underwent baseline, early and interim 18F-FDG PET/CT scans. Five-point and % ΔSUVmax criteria were used separately to interpret 18F- FDG PET/CT images. Interobserver reproducibility was assessed with the kappa test （κ）, and thresholds of %ΔSUVmax were calculated via receiver operating characteristic curve（ROC）. Survival curves were obtained using Kaplan-Meier curves and log-rank test. Cox regression analysis was used for multi-factor analysis. Results Median follow-up was 24 months （6 to 42 months）. The kappa value of the five-point scale was above 0.600 with the reference background set in the liver（Score≥4）. The optimal threshold of %ΔSUVmax was 81% for early PET/CT and 74% for interim PET/CT. Survival analysis showed both early and interim PET/CT scans could predict the outcome of 56 patients with DLBCL, and 3-year PFS and OS of PET-negative patients were significantly higher than those of PET-positive ones（P〈0.05）. Five-score criteria were more accurate in evaluating 3-year PFS of DLBCL patients in the interim PET/CT scan（76.79%）. %ΔSUVmax criteria were better for interpreting 3-year OS（76.79%and 83.93%）. Multi-factor analysis demonstrated that early and interim PET/CT were solid predicting factors for DLBCL patients. Conclusions Early and interim PET/CT scans could predict the outcome of patients with DLBCL, treated with R-CHOP/CHOP. Three-year OS was more accurate in early and interim PET/CT using 66%ΔSUVmax criteria as an interpretation, while 3-year PFS was more accurate in interim PET/CT by five scores criteria.