Nawara C, Rendl G, Wurstbauer K, Lackner B, Rettenbacher L, Datz L, Studnicka M, Sedlmayer F, Pirich C
Department of Nuclear Medicine and Endocrinology, Paracelsus Medical University, Salzburg, Austria.
Q J Nucl Med Mol Imaging. 2012 Apr;56(2):191-201. Epub 2012 Mar 9.
18F fluoro-deoxy-glucose (FDG) positron emission tomography (PET)-imaging improves the diagnostic accuracy in staging non small cell lung cancer (NSCLC) with possible impact on survival. This prospective study aimed to investigate the impact of PET and PET/CT on treatment planning and prognosis in patients with NSCLC treated with radiation therapy.
From October 2003 to January 2008, 91 consecutive patients with proven NSCLC stage T1-4N0-3M0 (clinical stages: I-IIIb) underwent accelerated, twice daily radiation therapy in target splitting technique. 70 patients received chemotherapy before radiation therapy (76%). All patients underwent PET or PET/CT-imaging and were followed up for a median time of 30 months. Imaging findings were interpreted visually and a SUV cut-off of 2.5 was applied for delineation of tumor borders. Changes in staging and planning treatment volumes (PTV) due to PET or PET/CT-imaging and survival were defined as primary study endpoints. The impact of tumor-type, stage, age, gender, weight loss and FDG-uptake in PET imaging as measured by the standardized uptake value (SUV) on survival were analysed as secondary endpoints.
PET imaging provided additional diagnostic information over CT alone in 20% (N.=18) of our study population, leading to upstaging in 17% of them, respectively. In 5 patients (5.5% of 91) atelectasis could be separated from tumor tissue, PTV was altered in 9% (N.=8). 39 patients (43%) died during the observation period, mean overall survival was 32.3 months (95% Confidence intervalI 27.6-37.1) and tumor specific survival was 36.9 months (95 % CI 32.0-42.0), respectively. One- and two year survival rates reached 90.1% and 67.7%, respectively. Multivariate analysis did not reveal any significant prognostic impact of tumor-type, stage, age, gender or FDG-uptake as given by SUVmax (mean 13.6±6.8) or SUVmean (mean 5.5±1.6).
The use of FDG-PET- and PET/CT-imaging provided incremental information relevant for treatment-planning in about 10 % of patients with NSCLC undergoing accelerated radiation therapy with curative intent. This prospective trial did not provide evidence for the assumption that the SUV might be an independent predictor of outcome.
18F氟脱氧葡萄糖（FDG）正电子发射断层扫描（PET）成像可提高非小细胞肺癌（NSCLC）分期的诊断准确性，并可能对生存率产生影响。这项前瞻性研究旨在调查PET和PET/CT对接受放射治疗的NSCLC患者治疗计划和预后的影响。
从2003年10月至2008年1月，91例经证实为NSCLC的T1-4N0-3M0期（临床分期：I-IIIb）患者采用加速分割、每日两次的放射治疗，采用靶区分割技术。70例患者在放疗前接受了化疗（76%）。所有患者均接受了PET或PET/CT成像，并进行了中位时间为30个月的随访。影像学结果采用视觉解读，应用SUV截止值2.5来勾画肿瘤边界。将PET或PET/CT成像导致的分期和计划治疗体积（PTV）变化以及生存率定义为主要研究终点。将肿瘤类型、分期、年龄、性别、体重减轻以及PET成像中通过标准化摄取值（SUV）测量的FDG摄取对生存率的影响作为次要终点进行分析。
在我们的研究人群中，20%（n = 18）的患者PET成像比单独CT提供了更多诊断信息，其中17%的患者分期上调。5例患者（91例中的5.5%）的肺不张与肿瘤组织得以区分，8例患者（9%）的PTV发生改变。39例患者（43%）在观察期内死亡，平均总生存期为32.3个月（95%置信区间27.6 - 37.1），肿瘤特异性生存期为36.9个月（95%置信区间32.0 - 42.0）。1年和2年生存率分别达到90.1%和67.7%。多因素分析未显示肿瘤类型、分期、年龄、性别或SUVmax（平均13.6±6.8）或SUVmean（平均5.5±1.6）所反映的FDG摄取对预后有任何显著影响。
对于约10%接受根治性加速放疗的NSCLC患者，使用FDG-PET和PET/CT成像可提供与治疗计划相关的增量信息。这项前瞻性试验并未为SUV可能是预后独立预测指标这一假设提供证据。
