Department of Nuclear Medicine, PET/CT Centre, "Santa Maria della Misericordia" Hospital, Via Tre Martiri 140, 45100, Rovigo, Italy,
Eur J Nucl Med Mol Imaging. 2014 Jul;41(7):1293-300. doi: 10.1007/s00259-014-2720-z. Epub 2014 Feb 25.
To evaluate if the detection rate (DR) of (18)F-choline (18F-CH) PET/CT is influenced by androgen-deprivation therapy (ADT) in patients with prostate cancer (PC) already treated with radical intent and presenting biochemical relapse.
We have retrospectively evaluated (18)F-CH PET/CT scans of 325 consecutive PC patients enrolled in the period November 2009 to December 2012 previously treated with radical intent and referred to our centre to perform (18)F-CH PET/CT for biochemical relapse. Two different groups of patients were evaluated. group A included the whole sample of 325 patients (mean age 70 years, range: 49-86) who presented trigger PSA between 0.1 and 80 ng/ml (mean 5.5 ng/ml), and group B included 187 patients (mean age 70 years, range 49-86) with medium-low levels of trigger PSA ranging between 0.5 and 5 ng/ml (mean PSA 2.1 ng/ml); group B was chosen in order to obtain a more homogeneous group of patients in terms of PSA values also excluding both very low and very high PSA levels avoiding the "a priori" higher probability of negative or positive PET scan, respectively. At the time of examination, 139 patients from group A and 72 patients from group B were under ADT: these patients were considered to be hormone-resistant PC patients because from their oncologic history (>18 months) an increase of PSA levels emerged despite the ongoing ADT. The relationship between (18)F-CH PET/CT findings and possible clinical predictors was investigated using both univariate and multivariate binary logistic regression analyses, including trigger PSA and ADT.
Considering the whole population, overall DR of (18)F-CH PET was 58.2 % (189/325 patients). In the whole sample of patients (group A), both at the univariate and multivariate logistic regression analysis, trigger PSA and ADT were significantly correlated with the DR of (18)F-CH PET (p < 0.05). Moreover, the DR in patients under ADT (mean PSA 7.8 ng/ml) was higher than in patients not under ADT (mean PSA 3.9 ng/ml), (DR was 70.5 % and 48.9 %, respectively; p < 0.001), therefore, demonstrating the existence of a significant correlation between the DR of (18)F-CH PET and ADT. In group B patients only trigger PSA resulted a reliable predictor of the (18)F-CH positivity, since ADT was not correlated to the DR of (18)F-CH PET (p = 0.061). Also in group B the DR of (18)F-CH PET in patients under ADT was higher than in patients not under ADT (65.3 % and 51.3 %, respectively) but the difference was not significant without a statistically significant correlation in the Mann Whitney test (p = 0.456) therefore, suggesting the lack of correlation between DR (18)F-CH PET/CT and ADT.
Similarly to previous published studies, in our series the overall DR of (18)F-CH PET/CT was 58 % and was significantly correlated to trigger PSA. The most important finding of the present study is that ADT does not negatively influence DR of (18)F-CH PET/CT in PC patients with biochemical relapse; therefore, it can be suggested that it is not necessary to withdraw ADT before performing (18)F-CH PET/CT.
评估前列腺癌（PC）患者在接受根治性治疗后出现生化复发并接受雄激素剥夺治疗（ADT）时，（18）F-胆碱（18F-CH）PET/CT 的检测率（DR）是否受到影响。
我们回顾性评估了 2009 年 11 月至 2012 年 12 月期间 325 例连续接受根治性治疗并因生化复发来我院行（18）F-CH PET/CT 的 PC 患者的（18）F-CH PET/CT 扫描。评估了两组不同的患者。A 组包括 325 例患者（平均年龄 70 岁，范围：49-86），其触发 PSA 介于 0.1 和 80ng/ml 之间（平均 PSA 5.5ng/ml）；B 组包括 187 例患者（平均年龄 70 岁，范围 49-86），其触发 PSA 处于中低水平，介于 0.5 和 5ng/ml 之间（平均 PSA 2.1ng/ml）；选择 B 组是为了获得一组 PSA 值更均匀的患者，同时排除了 PSA 值极低和极高的患者，从而避免了 PET 扫描的假阴性或假阳性的“先验”概率更高。在检查时，A 组中有 139 例患者和 B 组中有 72 例患者正在接受 ADT：这些患者被认为是激素抵抗性 PC 患者，因为从他们的肿瘤病史（>18 个月）来看，尽管持续进行 ADT，PSA 水平仍有升高。使用单变量和多变量二元逻辑回归分析，包括触发 PSA 和 ADT，研究了（18）F-CH PET/CT 结果与可能的临床预测因素之间的关系。
考虑到整个人群，（18）F-CH PET 的总体 DR 为 58.2%（189/325 例患者）。在整个患者样本（A 组）中，无论是在单变量还是多变量逻辑回归分析中，触发 PSA 和 ADT 与（18）F-CH PET 的 DR 均呈显著相关（p<0.05）。此外，接受 ADT 的患者（平均 PSA 7.8ng/ml）的 DR 高于未接受 ADT 的患者（平均 PSA 3.9ng/ml），（DR 分别为 70.5%和 48.9%，p<0.001），因此，这表明（18）F-CH PET 的 DR 与 ADT 之间存在显著的相关性。在 B 组患者中，只有触发 PSA 是（18）F-CH 阳性的可靠预测因子，因为 ADT 与（18）F-CH PET 的 DR 无关（p=0.061）。同样在 B 组中，接受 ADT 的患者的（18）F-CH PET 的 DR 高于未接受 ADT 的患者（分别为 65.3%和 51.3%），但在曼-惠特尼检验中差异无统计学意义（p=0.456），因此，这表明（18）F-CH PET/CT 的 DR 与 ADT 之间缺乏相关性。
与之前发表的研究类似，在我们的研究系列中，（18）F-CH PET/CT 的总体 DR 为 58%，与触发 PSA 显著相关。本研究的最重要发现是，ADT 不会降低生化复发的 PC 患者（18）F-CH PET/CT 的 DR；因此，建议在进行（18）F-CH PET/CT 之前不必停止 ADT。
