Lopci Egesta, Zucali Paolo Andrea, Ceresoli Giovanni Luca, Perrino Matteo, Giordano Laura, Gianoncelli Letizia, Lorenzi Elena, Gemelli Maria, Santoro Armando, Chiti Arturo
Nuclear Medicine Department, Humanitas Research Hospital, Rozzano, Milan, Italy,
Eur J Nucl Med Mol Imaging. 2015 Apr;42(5):667-75. doi: 10.1007/s00259-014-2960-y. Epub 2014 Nov 18.
Quantitative analyses on FDG PET for response assessment are increasingly used in clinical studies, particularly with respect to tumours in which radiological assessment is challenging and complete metabolic response is rarely achieved after treatment. A typical example is malignant pleural mesothelioma (MPM), an aggressive tumour originating from mesothelial cells of the pleura. We present our results concerning the use of semiquantitative and quantitative parameters, evaluated at the baseline and interim PET examinations, for the prediction of treatment response and disease outcome in patients with MPM.
We retrospectively analysed data derived from 131 patients (88 men, 43 women; mean age 66 years) with MPM who were referred to our institution for treatment between May 2004 and July 2013. Patients were investigated using FDG PET at baseline and after two cycles of pemetrexed-based chemotherapy. Responses were determined using modified RECIST criteria based on the best CT response after treatment. Disease control rate, progression-free survival (PFS) and overall survival (OS) were calculated for the whole population and were correlated with semiquantitative and quantitative parameters evaluated at the baseline and interim PET examinations; these included SUVmax, total lesion glycolysis (TLG), percentage change in SUVmax (ΔSUVmax) and percentage change in TLG (ΔTLG).
Disease control was achieved in 84.7 % of the patients, and median PFS and OS for the entire cohort were 7.2 and 14.3 months, respectively. The log-rank test showed a statistically significant difference in PFS between patients with radiological progression and those with partial response (PR) or stable disease (SD) (1.8 vs. 8.6 months, p < 0.001). Baseline SUVmax and TLG showed a statistically significant correlation with PFS and OS (p < 0.001). In the entire population, both ΔSUVmax and ΔTLG were correlated with disease control based on best CT response (p < 0.001). ΔSUVmax was significantly correlated with PFS in the entire population (p = 0.02) and with both PFS and OS in patients not undergoing talc pleurodesis (n = 65; p < 0.01 for PFS, p = 0.03 for OS), and in patients without pleurodesis presenting a SD and/or PR at CT after two cycles.
These results confirm the role of FDG PET in the assessment of disease prognosis and treatment efficacy in MPM patients receiving first-line pemetrexed-based chemotherapy. In particular, metabolic response evaluated using ΔSUVmax can be used to predict outcome in MPM patients not undergoing talc pleurodesis who achieve SD and/or PR at the interim CT evaluation.
在临床研究中，越来越多地使用氟代脱氧葡萄糖正电子发射断层扫描（FDG PET）进行定量分析以评估疗效，特别是对于那些放射学评估具有挑战性且治疗后很少能实现完全代谢缓解的肿瘤。一个典型的例子是恶性胸膜间皮瘤（MPM），这是一种起源于胸膜间皮细胞的侵袭性肿瘤。我们展示了关于在基线和中期PET检查时评估的半定量和定量参数用于预测MPM患者治疗反应和疾病转归的结果。
我们回顾性分析了2004年5月至2013年7月间因MPM转诊至我院接受治疗的131例患者（88例男性，43例女性；平均年龄66岁）的数据。患者在基线时以及基于培美曲塞的化疗两个周期后接受FDG PET检查。根据治疗后最佳CT反应，使用改良的实体瘤疗效评价标准（RECIST）确定反应。计算了整个人群的疾病控制率、无进展生存期（PFS）和总生存期（OS），并将其与在基线和中期PET检查时评估的半定量和定量参数相关联；这些参数包括最大标准化摄取值（SUVmax）、总病灶糖酵解（TLG）、SUVmax的百分比变化（ΔSUVmax）和TLG的百分比变化（ΔTLG）。
84.7%的患者实现了疾病控制，整个队列的中位PFS和OS分别为7.2个月和14.3个月。对数秩检验显示，放射学进展患者与部分缓解（PR）或疾病稳定（SD）患者的PFS存在统计学显著差异（1.8个月对8.6个月，p＜0.001）。基线SUVmax和TLG与PFS和OS存在统计学显著相关性（p＜0.001）。在整个人群中，ΔSUVmax和ΔTLG均与基于最佳CT反应的疾病控制相关（p＜0.001）。ΔSUVmax在整个人群中与PFS显著相关（p = 0.02），在未进行滑石粉胸膜固定术的患者（n = 65；PFS为p＜0.01，OS为p = 0.03）以及在两个周期后CT显示为SD和/或PR且未进行胸膜固定术的患者中与PFS和OS均显著相关。
这些结果证实了FDG PET在评估接受一线基于培美曲塞化疗的MPM患者疾病预后和治疗疗效中的作用。特别是，使用ΔSUVmax评估的代谢反应可用于预测在中期CT评估中达到SD和/或PR且未进行滑石粉胸膜固定术的MPM患者的预后。
