^11C-胆碱PET显像的临床初步应用

目的: 初步探讨11C-胆碱PET显像诊断体内占位病变的良恶性价值.材料和方法: 对3例脑内、14例肺内占位病变患者同时行N-甲基-11C胆碱(11C-胆碱)和18F-FDG PET显像,ROI方法测定最大标准摄取值(SUVmax).结果: 13处恶性占位病灶11C-胆碱PET显像均为阳性;但病灶大小与SUVmax间无明显相关性.8处良性占位病灶,18F-FDG均为假阳性,11C-胆碱PET显像仅有1例为假阳性.11C -胆碱显像漏检1处肺癌肾上腺转移病灶.结论: 11C-胆碱PET显像可能成为肿瘤良恶性鉴别的可靠方法.     

11C-胆碱和18F-FDG在肿瘤PET中的比较

11C-胆碱是最近研制的一种正电子肿瘤阳性显像剂,在肿瘤/非靶组织的比值高于18F-FDG,特别在脑肿瘤和前列腺癌显像方面较18F-FDG显示出优势.11C-胆碱和18F-FDG在脑肿瘤、肺癌、食道癌和前列腺癌的诊断方面各有优劣,两者的摄取机理与显像方法也不同.除了11C-胆碱,还有18F-氟代胆碱(18F-fluorocholine),其临床价值有待更多的研究来证实.     

11C标记的放射性药物在PET-CT肿瘤诊断上的应用

18F-氟代脱氧葡萄糖（18F-FDG）是目前最常用的肿瘤诊断药物,但由于其正常的生理分布,影响了一些肿瘤的诊断.本文主要介绍了11C标记的正电子药物：11C-甲硫氨酸、11C-胆碱、11C-乙酸盐在原发脑肿瘤、头颈部肿瘤、肺癌、肝癌、妇科肿瘤、前列腺癌、膀胱癌、骨及软组织肿瘤上诊断及分期、疗效监测的价值.研究表明,11C标记的肿瘤正电子药物是18F-FDG的一个重要补充.     

PET在前列腺癌中的应用

前列腺癌是老年男性最常见的恶性肿瘤之一,PET在其早期诊断和准确分期方面具有重要价值。18F-氟代脱氧葡萄糖(18F-FDG)PET对前列腺癌的检出并不敏感,也不能可靠进行淋巴结分期,但18F-FDG摄取与疾病进展程度相关。11C-胆碱PET诊断前列腺癌的准确率高,在淋巴结及骨转移的检出方面也明显优于18F-FDGPET,但其半衰期短而限制了临床应用。18F-胆碱的肿瘤摄取与11C-胆碱相似,但在泌尿系统排泄较高。其他示踪剂如11C-乙酸、11C-甲硫氨酸、18F标记的雄激素等在前列腺癌的诊断、分期及疗效评价方面也具有一定价值。     

11C标记的放射性药物在PET-CT肿瘤诊断上的应用

18F-氟代脱氧葡萄糖(18F-FDG)是目前最常用的肿瘤诊断药物,但由于其正常的生理分布,影响了一些肿瘤的诊断。本文主要介绍了11C标记的正电子药物:11C-甲硫氨酸、11C-胆碱、11C-乙酸盐在原发脑肿瘤、头颈部肿瘤、肺癌、肝癌、妇科肿瘤、前列腺癌、膀胱癌、骨及软组织肿瘤上诊断及分期、疗效监测的价值。研究表明,11C标记的肿瘤正电子药物是18F-FDG的一个重要补充。     

脑胶质瘤的11C-甲硫氨酸和11C-胆碱PET和PET-CT

18F-氟脱氧葡萄糖(18F-FDG)在脑肿瘤检查中较常用的诊断用显像剂,但由于其正常的生理分布和自身的缺点影响了其在胶质瘤术前尤其是治疗后的诊断和评估.研究表明,11C标记的甲硫氨酸(11C-MET)和胆碱(11C-胆碱)在脑胶质瘤PET和PET-CT检查中的术前诊断价值、疗效监测以及治疗后肿瘤复发或残存与放射性坏死或治疗后反应的鉴别和评估方面克服了18F-FDG的局限性,是18F-FDG PET和PET-CT的一个重要替代或补充.     

11C-胆碱PET/CT显像在前列腺良恶性病变鉴别诊断中的应用

目的 探讨11C-胆碱PET/CT显像在前列腺良恶性病变鉴别诊断中的作用.方法 前列腺病变患者45例,按体重静脉注射7.4 MBq/kg 11C-胆碱5 min后行仰卧位盆腔PET/CT显像,可疑转移患者行全身显像.测量前列腺病灶(靶)及肌肉(非靶)组织的最高标准摄取值(SUVmax),并计算其比值(P/M).结果 病理检查证实前列腺良性病变27例,前列腺癌18例.前列腺良恶性病变的P/M比值间差异有显著性(1.87±1.21与4.02±1.88,t=2.07,P＜0.01).以P/M比值＞2.32为标准,11C-胆碱PET/CT显像诊断前列腺癌的灵敏度为88.89%,特异性为88.89%,阴性预测值为92.31%.结论 11C-胆碱PET/CT显像是一种诊断前列腺癌较好的无创性检查方法;P/M比值比SUV能更好鉴别前列腺良恶性病变.     

MRI、MRS及11C-胆碱PET/CT对前列腺癌诊断的对比研究

目的 探讨11C-胆碱PET/CT对前列腺癌的诊断价值,并与常规MRI及直肠线圈1H MR波谱分析(MRS)的诊断结果对比.方法 34例前列腺病变患者行11C-胆碱PET/CT、常规前列腺MRI及直肠线圈MRS检查.11C-胆碱PET/CT图像于注射5 min后获取.对前列腺良性病变和前列腺癌部位分别计算标准摄取值(SUV)最大值及平均值(SUVmax、SUVmean).将PET/CT诊断结果与MRI、1H MRS及病理检查结果对比.分析SUV与血清前列腺特异抗原(PSA)的相关性.病理检查结果为在开放式MR光学导引系统下穿刺活组织检查或经直肠指诊穿刺获得.转移灶经局部穿刺活组织检查或影像学随访证实.统计学处理采用SPSS 11.0软件.结果 (1)原发性前列腺癌SUVmax 5.72±2.31,SUVmean 4.78±2.20.SUV比较:低分化腺癌＞中分化腺癌＞高分化腺癌.前列腺良性病变的SUVmax 2.49±1.43,SUVmean 1.89±1.24.不同病理类型及分化程度的前列腺病变SUVmax、SUVmean之间差异无统计学意义(FSUVmax=2.401,FSUVmean=1.744;P＞0.05).前列腺癌SUV高于前列腺良性病变,但二者存在交叉重叠现象,如果以SUVmax 2.5为分界,则二者之间有25.8%(8/31)交叉.因此,前列腺的形态、前列腺内放射性分布的均匀程度对前列腺癌的诊断价值高于SUV.SUVmax与血清PSA之间呈正相关(等级相关系数rs=0.819 86,P＜0.01).(2)影像诊断与病理检查结果符合的例数11C-胆碱PET/CT为25例,MRI为21例,MRS为22例.11C-胆碱PET/CT、MRI及MRS诊断前列腺癌的灵敏度、特异性、阳性预测值、阴性预测值分别为 93.75%, 66.67%, 75.00%, 90.91%; 87.50%, 46.67%, 63.64%, 77.78%; 87.50%, 53.33%, 66.67%, 80.00%.3种方法比较差异无统计学意义(χ2=1.422,P＞0.05).(3)11C-胆碱PET/CT能区别前列腺癌治疗后复查患者复发区与治疗有效区,并可检出远处转移灶.结论 11C-胆碱PET/CT可用于前列腺癌的诊断、分期及检测复发和转移灶;其对前列腺癌的诊断灵敏度、特异性、阳性预测值、阴性预测值均略高于MRS及MRI;SUVmax与血清PSA之间呈正相关.     

11 C-胆碱PET/CT显像在PSA升高的前列腺病变中的应用价值

目的：探讨11C-胆碱PET/CT显像在PSA升高的前列腺良恶性病变中鉴别诊断及术前分期的应用价值。方法：PSA升高的前列腺病变患者40例,静脉注射0.2mli/kg11C-胆碱5min后行仰卧位盆腔PET/CT显像,必要时加做全身显像。测量病变组织与对照组织的最高SUV（SUVmax）,并计算其比值（P/M）,通过半定量法分析显像结果。结果：病理证实前列腺增生及炎症共17例,前列腺癌23例。前列腺良恶性病变的P/M值之间的差异具有显著性。以P/M＆gt;2.14为标准,11C-胆碱PET/CT显像诊断前列腺癌的灵敏度为86.96%,特异性为88.24%,阳性预测值为90.91%。PET/CT同时发现了6例患者的盆腔淋巴结转移,4例骨转移,1例肺转移。结论：对于PSA升高的前列腺病变,11C-胆碱PET/CT显像不仅是一种鉴别良恶性的较好的无创性检查方法,而且可以有助于准确术前分期。     

原发性前列腺癌病人术前淋巴结分期:扩散加权成像和~(11)C-胆碱PET/CT定量成像参数的比较和相关分析

正摘要目的比较DWI和11C-胆碱PET/CT在原发性前列腺癌病人术前淋巴结定性中的诊断价值。方法 33例前列腺癌病人在前列腺切除术和扩大盆腔淋巴结清扫术前均行     

Imaging prostate cancer

In the detection of prostate cancer, the most important role of imaging is ultrasound-guided prostatic biopsy. In the staging evaluation of prostate cancer, each presently used modality--transrectal US (TRUS), MR imaging, CT, nuclear medicine, and positron emission tomography--has advantages and disadvantages. Evidence-based guidelines on the use of CT and nuclear medicine bone scan, in assessing the risk of distant spread of prostate cancer, are available. There is no consensus and there are no guidelines, however, for the use of imaging in the evaluation of prostate cancer local tumor extent. Results on the value of TRUS vary widely, and prospective multicenter studies suggest that TRUS is no better than digital rectal examination in predicting extracapsular extension. MR imaging offers the most promise for local staging of prostate cancer, but it must resolve problems of reproducible image quality and interobserver variability, and it should prove its efficacy in multicenter trials before it can be recommended for general clinical use. The introduction of MR spectroscopic imaging further expands the value of MR imaging, offering anatomic and metabolic evaluation of prostate cancer.     

Combined 18F-FDG and 11C-methionine PET scans in patients with newly progressive metastatic prostate cancer.

Metastatic prostate cancer may respond initially to hormone suppression, with involution of tumor sites, but ultimate tumor progression is inevitable. Our aim was to detect the proportion of bone and soft-tissue lesions that represent metabolically active tumor sites in patients with progressive metastatic prostate cancer. METHODS: In a prospective study, we compared 18F-FDG and L-methyl-11C-methionine (11C-methionine) PET with conventional imaging modalities (CIM), which included the combination of 99mTc-methylene diphosphonate scintigraphy, CT, or MRI. Twelve patients with prostate cancer, increasing levels of prostate-specific antigen (PSA), and at least 1 site (index lesion) with new or increasing disease on CIM were studied. The total numbers of soft-tissue and bone-tissue lesions, in a site-by-site comparison, were calculated for all imaging modalities. RESULTS: The sensitivities of 18F-FDG PET and 11C-methionine PET were 48% (167/348 lesions) and 72.1% (251/348 lesions), respectively, with CIM being used as the 100% reference (348/348). 11C-Methionine PET identified significantly more lesions than 18F-FDG PET (P < 0.01). All 12 patients with progressive metastatic prostate cancer had at least 1 lesion site of active metabolism for 18F-FDG or 11C-methionine, which could be used as an index lesion to monitor the metabolic response to therapy. A significant proportion of lesions (26%) had no detectable metabolism of 18F-FDG or 11C-methionine. Although technical factors cannot be totally excluded, we believe that metabolically inactive sites may be necrotic or dormant. More than 95% (251/258) of metabolically active sites (72% of the total number of lesions detected by CIM) metabolize 11C-methionine. 18F-FDG uptake is more variable, with 65% of metabolically active sites (48% of the total number of lesions detected by CIM). CONCLUSION: These findings reflect the different biologic characteristics of the lesions in a heterogeneous tumor such as prostate cancer and suggest that a time-dependent metabolic cascade may occur in advanced prostate cancer, with initial uptake of 11C-methionine in dormant sites followed by increased uptake of 18F-FDG during progression of disease.     

[C]choline as a potential PET marker for imaging of breast cancer athymic mice

[¹¹C]Choline has been evaluated as a potential positron emission tomography (PET) marker for imaging of breast cancer. The biodistribution of [¹¹C]choline was determined at 45 min post iv injection in MCF-7’s transfected with IL-1alpha implanted athymic mice and MDA-MB-435 implanted athymic mice. The results showed the uptake of [¹¹C]choline in these tumors was high, 2.0% dose/g in MCF-7’s transfected with IL-1alpha implanted mice and 1.8% dose/g in MDA-MB-435 implanted mice; the ratios of tumor/muscle (T/M) and tumor/blood (T/B) were 1.7 (T/M, MCF-7’s), 2.1 (T/M, MDA-MB-435) and 6.9 (T/B, MCF-7’s), 12.5 (T/B, MDA-MB-435), respectively; the tumor/muscle ratios are moderate, and the tumor/blood ratios are high. The micro-PET imaging of [¹¹C]choline in both breast cancer athymic mice was acquired for 15 min from a MCF-7’s transfected with IL-1alpha and/or MDA-MB-435 implanted mouse at 45 min post iv injection of 1 mCi of the tracer using a dedicated high resolution (<3 mm full-width at half-maximum) small FOV (field-of-view) PET imaging system, Indy-PET II scanner, developed in our laboratory, which showed the uptake of [¹¹C]choline in MCF-7’s transfected with IL-1alpha tumor or MDA-MB-435 tumor implanted in a nude athymic mouse. These results suggest that [¹¹C]choline may be a potential PET breast cancer imaging agent.     

Local detection of prostate cancer by positron emission tomography with 2-fluorodeoxyglucose: comparison of filtered back projection and iterative reconstruction with segmented attenuation correction.

BACKGROUND: To compare filtered back projection (FBP) and iterative reconstruction with segmented attenuation correction (IRSAC) in the local imaging of prostate cancer by positron emission tomography with 2-fluorodeoxyglucose (FDG-PET). METHODS: We retrospectively identified 13 patients with primary (n=7) or recurrent (n=6) prostate cancer who had increased uptake in the prostate on FDG-PET performed without urinary catheterization, contemporaneous biopsy confirming the presence of active tumor in the prostate, and correlative cross-sectional imaging by MRI (n=8) or CT (n=5). FDG-PET images were reconstructed by FBP and IRSAC. Two independent nuclear medicine physicians separately rated FBP and IRSAC images for visualization of prostatic activity on a 4-point scale. Results were compared using biopsy and cross-sectional imaging findings as the standard of reference. RESULTS: IRSAC images were significantly better that FBP in terms of visualization of prostatic activity in 12 of 13 patients, and were equivalent in 1 patient (p<0.001, Wilcoxon signed ranks test). In particular, 2 foci of tumor activity in 2 different patients seen on IRSAC images were not visible on FBP images. In 11 patients who had a gross tumor mass evident on cross-sectional imaging, there was good agreement between PET and cross-sectional anatomic imaging with respect to tumor localization. CONCLUSIONS: In selected patients, cancer can be imaged within the prostate using FDG-PET, and IRSAC is superior to FBP in image reconstruction for local tumor visualization.     

Prostate cancer: a comparative study of 11C-choline PET and MR imaging combined with proton MR spectroscopy

Purpose Prostate cancer is difficult to visualise in its early stages using current imaging technology. The present study aimed to clarify the utility of ¹¹C-choline PET for localising and evaluating cancer lesions in patients with prostate cancer by conducting a prospective comparison with magnetic resonance (MR) imaging combined with proton MR spectroscopy.Methods PET and MR imaging combined with proton MR spectroscopy were performed in 20 patients with prostate cancer. Correlations among the metabolite ratio of choline + creatine to citrate (Cho+Cr/Ci) on MR spectroscopy, serum PSA and maximum standardised uptake value (SUV_max) of ¹¹C-choline were assessed. The location of the primary lesion was assessed by the site of SUV_max and the laterality of the highest Cho+Cr/Ci ratio and confirmed by examination of surgical pathology specimens (n=16).Results PET exhibited a diagnostic sensitivity of 100% (20/20) for primary lesions, while the sensitivities of MR imaging and MR spectroscopy were 60% (12/20) and 65% (13/20), respectively. Weak linear correlations were observed between SUV_max and serum PSA (r=0.52, p<0.05), and between SUV_max and Cho+Cr/Ci ratio (r=0.49, p<0.05). Regarding the localisation of main primary lesions, PET results agreed with pathological findings in 13 patients (81%) (=0.59), while MR spectroscopy results were in accordance with pathological findings in eight patients (50%) (=0.11).Conclusion This preliminary study suggests that ¹¹C-choline PET may provide more accurate information regarding the localisation of main primary prostate cancer lesions than MR imaging/MR spectroscopy. A further clinical study of ¹¹C-choline PET in a large number of patients suspected of prostate cancer will be necessary to determine the clinical utility of ¹¹C-choline PET in patients who clinically require biopsy.     

MR imaging of treated prostate cancer

Many management options are available to patients with newly diagnosed prostate cancer. Magnetic resonance (MR) imaging plays an important role in initial staging of prostate cancer, but it also aids in tumor detection when there is clinical or biochemical suspicion of residual or recurrent disease after treatment. The purpose of this review is to describe the normal appearances of the prostatic region after different kinds of treatment for prostate cancer and to discuss how these appearances differ from those of recurrent and residual disease. Several MR imaging techniques used in evaluating patients with prostate cancer are described, including conventional MR imaging sequences (mainly T1- and T2-weighted sequences), MR spectroscopic imaging, diffusion-weighted imaging, and dynamic contrast agent-enhanced MR imaging. Clinical considerations, together with the different approaches for interpreting serum prostate-specific antigen values in the posttreatment setting, are also presented. All forms of treatment alter the MR imaging features of the prostatic region to a greater or lesser extent, and it is important to be able to recognize expected posttreatment appearances and distinguish them from the features of recurrent or residual cancer to aid subsequent clinical management.     

PET-imaging in tumors of the reproductive trac.

There is increasing evidence that metabolic imaging with positron-emission tomography (PET) using fluor-18 labeled fluorodeoxyglucose (18F FDG) is highly accurate for in vivo detection of a variety of malignancies. This quality gives FDG-PET an important role in the detection of malignant tumors and their metastases as well as for differentiation of tumors of unknown etiology. In the male and female reproductive tract, whole body imaging with FDG-PET is in particular capable of visualizing lymph-node and distant metastases before these changes become apparent on conventional cross-sectional imaging modalities. According to the incidence of tumors in the reproductive tract, FDG-PET-imaging has been evaluated in prostate cancer, ovarian cancer, cervical and testicular cancer. The role of PET is discussed with respect to the current management of patients. The presented data indicate that FDG-PET is more accurate for lymph-node staging in cervical cancer and testicular cancer. In ovarian cancer, FDG-PET may be helpful for detection of tumor recurrence. The role of FDG-PET is questionable in prostate cancer, due to the low metabolic activity of this type of cancer. Carbon-11 labeled acetate and carbon-11 or fluor-18 labeled choline are more promising than FDG for detection of recurrence in prostate cancer. In all other tumors of the reproductive tract there is limited experience with PET for a final conclusion.     

11C—甲硫氨酸PET在乳腺癌诊疗中的价值

乳腺癌是我国妇女最常见的恶性肿瘤之一,也是妇女中除肺癌外病死率最高的恶性肿瘤,早期诊断是降低乳腺癌病死率的关键因素.目前,乳腺癌的诊断方法主要是钼靶X线乳腺摄影、超声检查、磁共振成像、细针穿刺活组织检查等.乳腺癌的基因变化导致癌肿血流增加,葡萄糖代谢、氨基酸转运、蛋白质合成、受体表达增加,DNA合成和细胞增殖活跃,并诱导细胞凋亡.PET结果显示.肿瘤部位对18F-氟脱氧葡萄糖(18F-FDG)和11C-甲硫氨酸(11C-MET)摄取均增高而11C-MET合成方便快捷,价格较18F-FDG低,其在乳腺癌中的应用价值国外已有诸多报道.     

Localization of prostate cancer using 3T MRI: comparison of T2-weighted and dynamic contrast-enhanced imaging

OBJECTIVE: To compare dynamic contrast-enhanced imaging and T2-weighted imaging using a 3T MR unit for the localization of prostate cancer. METHODS: Twenty consecutive patients with biopsy-proven prostate cancer underwent both T2-weighted imaging and dynamic contrast-enhanced imaging. At T2-weighted imaging and dynamic contrast-enhanced imaging, the presence or absence of prostate cancer confined within the prostate without extracapsular or adjacent organ invasion was evaluated in the peripheral zones of base, mid-gland, and apex on each side. Final decisions on prostate cancer localization were made by consensus between two radiologists. Degrees of depiction of tumor borders were graded as poor, fair, or excellent. RESULTS: Prostate cancer was pathologically detected in 64 (53%) of 120 peripheral zone areas. The sensitivity, specificity, and accuracy for prostate cancer detection were 55%, 88% and 70% for T2-weighted imaging and 73%, 77%, and 75% for dynamic contrast-enhanced imaging, respectively. Three cancer areas were detected only by T2-weighted imaging, 15 only by dynamic contrast-enhanced imaging, and 34 by both T2-weighted imaging and dynamic contrast-enhanced imaging. A fair or excellent degree at depicting tumor border was achieved in 67% by T2-weighted imaging and in 90% by dynamic contrast-enhanced imaging (P<0.05). CONCLUSIONS: Dynamic contrast-enhanced imaging at 3T MRI is superior to T2-weighted imaging for the detection and depiction of prostate cancer and thus is likely to be more useful for preoperative staging.