Giovacchini G, Breeuwsma A J
Department of Radio-Oncology and Nuclear Medicine, Stadtspital Triemli, Zurich, Switzerland.
Q J Nucl Med Mol Imaging. 2012 Aug;56(4):354-66.
PET/CT with either [11C]choline or [18F]fluorocholine represents a powerful technique for restaging prostate cancer (PCa) patients with biochemical failure. The availability of dedicated PET/CT scanners allows fusioning of morphological and functional images, which enables accurate localization of sites of pathological tracer uptake and ease the differentiation between malignant and benign findings. A noteworthy advantage of this whole-body technique is that it provides information on multiple anatomic sites at a single time. As such, the technique has the capability of distinguishing between local relapse and distant metastases, and therefore has the potential to guide the medical treatment. The positive detection rate of [11C]choline PET/CT varies substantially in relation to the inclusion criteria. Studies which included unselected consecutive patients reported a positive detection rate ranging between 40% and 70%. Serum PSA level represents the single, most important factor affecting the rate of positive scans. Other positive predicitive factors include fast PSA kinetics (PSA velocity, PSA doubling time), advanced pathological state at initial staging, previous biochemical failure, hormone resistance and older age. Recent studies indicate that [11C]choline PET/CT has the potential to early restaging PCa patients for PSA levels lower than 1-1.5 ng/mL. However, more studies are necessary to better define the potential of this technique for low PSA levels. The previously cited risk factors can be used to identify patients that are at greater risk and that might best benefit from PET/CT scans. Patients that develop biochemical failure during androgen deprivation therapy (hormone resistance) have a higher likelihood for a positive [11C]choline PET/CT scan in comparison to patients that are drug naïve (hormone sensitive) and are not required to withdraw the anti-androgenic treatment before PET/CT.
使用[11C]胆碱或[18F]氟胆碱的PET/CT是对生化复发的前列腺癌（PCa）患者进行再分期的有力技术。专用PET/CT扫描仪的应用使得形态学和功能图像能够融合，这有助于准确确定病理性示踪剂摄取部位，并便于区分恶性和良性病变。这种全身技术的一个显著优点是它能一次性提供多个解剖部位的信息。因此，该技术有能力区分局部复发和远处转移，从而有可能指导医学治疗。[11C]胆碱PET/CT的阳性检出率因纳入标准的不同而有很大差异。纳入未经选择的连续患者的研究报告阳性检出率在40%至70%之间。血清PSA水平是影响阳性扫描率的唯一最重要因素。其他阳性预测因素包括快速的PSA动力学（PSA速度、PSA倍增时间）、初始分期时的晚期病理状态、既往生化复发、激素抵抗和高龄。最近的研究表明，[11C]胆碱PET/CT有可能对PSA水平低于1 - 1.5 ng/mL的PCa患者进行早期再分期。然而，需要更多研究来更好地确定该技术在低PSA水平时的潜力。前面提到的风险因素可用于识别风险较高且可能从PET/CT扫描中获益最大的患者。与未接受过治疗（激素敏感）的患者相比，在雄激素剥夺治疗期间出现生化复发（激素抵抗）的患者进行[11C]胆碱PET/CT扫描呈阳性的可能性更高，且在PET/CT检查前无需停用抗雄激素治疗。
