18F-前列腺特异性膜抗原-1007 PET/CT显像、11C-胆碱PET/CT显像及单光子发射计算机断层成像术骨显像对前列腺癌骨转移的诊断价值比较

目的探讨¹⁸F-前列腺特异性膜抗原(PSMA)-1007标记的正电子发射体层显像融合计算机体层显像技术(PET/CT)显像、11C-胆碱(11C-CHO)PET/CT显像及单光子发射计算机断层成像术(SPECT)骨显像在前列腺癌骨转移诊断上的差异。方法回顾性分析2018年9月至2020年7月北部战区总医院核医学科收治的43例男性前列腺癌患者的临床资料,年龄(77.47±11.87)岁,年龄范围为55~89岁。所有患者行¹⁸F-PSMA-1007 PET/CT显像、11C-CHO PET/CT显像及SPECT骨显像检查。分别统计¹⁸F-PSMA-1007 PET/CT显像、11C-CHO PET/CT及SPECT骨显像诊断骨转移的阳性例数和阴性例数,计算三种方法各自的灵敏度、特异度、准确性、阳性预测值、阴性预测值,绘制受试者工作特征(ROC)曲线,计算并比较各自曲线下面积(AUC),评价三种检查方法对前列腺癌骨转移的诊断效能。结果 43例前列腺癌患者中,27例患者出现骨转移。¹⁸F-PSMA-1007 PET/CT显像示26例患者发生骨转移,漏诊1例;11C-CHO PET/CT显像示24例患者发生骨转移,误诊1例,漏诊4例;SPECT骨显像示23例患者发生骨转移,误诊3例,漏诊7例,三者诊断前列腺癌骨转移的灵敏度、特异度、准确性分别为96.3%(26/27)、100%(16/16)、97.7%(42/43);85.2%(23/27)、93.8%(15/16)、88.4%(38/43);74.1%(20/27)、81.3%(13/16)、76.7%(33/43)。¹⁸F-PSMA-1007 PET/CT显像、11C-CHO PET/CT和SPECT骨显像ROC曲线的AUC和95%CI分别为0.981(0.885~1.000)、0.913(0.763~0.967)、0.777(0.624~0.889)。三种检查的AUC曲线下面积进行两两比较,差异均有统计学意义(P<0.05)。采用Wilcoxon秩和检验对27例患者三种方法检出的骨转移灶的数量进行两两比较发现,¹⁸F-PSMA-1007 PET/CT显像与SPECT骨显像比较,差异有统计学意义(Z=-2.484,P=0.013),¹⁸F-PSMA-1007 PET/CT显像与11C-CHO PET/CT显像比较,差异无统计学意义(Z=-0.160,P=0.873);11C-CHO PET/CT显像与SPECT骨显像比较,差异有统计学意义(Z=-2.085,P=0.037)。结论 PET/CT显像较SPECT骨显像能发现更多的骨转移灶。¹⁸F-PSMA-1007 PET/CT显像对前列腺癌骨转移诊断的灵敏度、特异度及准确性高于其他两种检查方式。在低前列腺特异性抗原(PSA)的情况下,能够精确地对前列腺癌骨转移做出诊断。     

Conventional imaging and 2-deoxy-2-[(18)F]fluoro-D-glucose positron emission tomography for predicting the clinical outcome of patients with previously treated Hodgkin's disease.

PURPOSE: The aim of this study was to determine the ability of 2-deoxy-2-[(18)F]fluoro-d-glucose positron emission tomography (FDG-PET) to predict the clinical outcome of previously treated patients with Hodgkin's Disease (HD). PATIENTS AND METHODS: Thirty-two patients were studied with PET within a median interval of 5.2 months after treatment. Conventional imaging (CI) performed within two months before PET included 2.9+/-1.2 imaging tests/patient. To determine the independent ability of FDG-PET to predict the clinical outcome, PET images were reread without knowledge of CI and clinical history. Study end points were disease-free survival, or clinical evidence of disease or death. PET and CI stages were also compared for each patient. RESULTS: Using the clinical outcome as gold standard after a median follow-up of 14 months, 21 of 32 patients (65%) were considered disease-free while 11 of 32 patients (35%) had evidence for disease or had died. The predictive accuracy of PET was 91% vs. 66% for conventional imaging (P<0.05). The positive predictive value (PPV) was also significantly higher for PET (79% vs. 50%, P<0.05), while its negative predictive value (NPV) tended to be higher than that of CI (100% vs. 86%, P=0.08). Kaplan-Meier analysis for disease-free survival showed a significant difference between PET-negative and -positive results. No such difference was observed between CI-positive and -negative results (P=0.35). CONCLUSION: Whole-body FDG-PET imaging modified the clinical stage in 28% of patients. Moreover, FDG-PET predicted patient outcome with a higher predictive accuracy than CI. This superior prognostic accuracy was achieved with a single FDG-PET study vs. 2.9+/-1.2 CI procedures/patient.     

Conventional imaging and 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography for predicting the clinical outcome of previously treated non-Hodgkin's lymphoma patients.

PURPOSE: The aim of this study was to determine the impact of positron emission tomography (PET) with 2-deoxy-2-[18F]fluoro-D-glucose (FDG) and combined conventional imaging on clinical stage and their ability to predict the clinical outcome of previously treated lymphoma patients. PROCEDURES: Seventy-eight patients with Non-Hodgkin's Lymphoma (NHL) were studied with PET within a median interval of 5.3 months after treatment. Conventional imaging performed after treatment and within three months before PET included 3.3+/-1.3 imaging tests/patient. To determine the independent ability of PET for predicting clinical outcome, PET images were re-read in a blinded fashion. Study endpoints were disease-free survival, or clinical evidence of disease or death. RESULTS: PET downstaged 18 patients, upstaged nine and revealed the same stage as conventional imaging in 51 patients. Using the clinical outcome as gold standard, the positive and negative predictive values of PET were 95% and 83% versus 72% and 67% for conventional imaging (P<0.05). The prognostic accuracy of PET was superior to that of conventional imaging (90 vs. 71%; P<0.05). Kaplan-Meier analysis for disease-free survival showed a significant difference between PET negative and PET positive results (P<0.0001). CONCLUSION: Whole-body FDG-PET imaging modified the clinical stage in 35% of lymphoma patients who were reevaluated after treatment. Moreover, FDG-PET predicted patient outcome with a higher predictive accuracy than conventional imaging. This superior prognostic accuracy was achieved with a single FDG-PET study versus multiple conventional imaging procedures/patient.     

2-deoxy-2-[F-18]fluoro-D-glucose imaging with positron emission tomography for initial staging of Hodgkin's disease and lymphoma.

PURPOSE: To assess the accuracy of 2-Deoxy-2-[F-18] Fluoro-D-Glucose positron emission imaging (FDG-PET) for staging Hodgkin's disease (HD) and non-Hodgkin's lymphoma (NHL) compared to conventional staging (CS) and to evaluate the impact on patient management. METHODS: Forty-five consecutive patients with lymphoma underwent whole-body FDG-PET imaging for initial staging. Discordant lesions were verified with biopsy or clinical follow-up. The impact on staging and management was reviewed retrospectively. RESULTS: A total of 129 sites of disease were identified, and 88 of those were concordant. FDG-PET and conventional staging demonstrated 24 and 17 additional sites, respectively. FDG-PET correctly upstaged five patients and down-staged two patients (16% total), leading to a change in therapy in 6/45 (13%) patients. However, FDG-PET understaged three patients (7%), correctly staged by conventional staging modalities. Assuming that the addition of FDG-PET to conventional staging modalities is 100% accurate for staging lymphoma, the accuracy of FDG-PET alone was 91%, compared to 84% for conventional staging modalities. CONCLUSIONS: FDG-PET is a noninvasive and efficient imaging modality for staging patients with lymphoma and should be used in conjunction with conventional staging modalities, as they appear complementary.     

正电子发射型断层成像在胃恶性肿瘤诊断中的作用

目的:评价正电子发射型断层扫描(PET)技术在胃恶性肿瘤中的诊断价值并与CT对照。方法:32例可疑胃恶性肿瘤患者术前行PET全身显像,22例行CT检查,将以上结果和病理分期对照。结果:32例中,25例为恶性肿瘤,7例为良性病变。18F-FDG-PET半定量分析对原发病灶的诊断敏感性、特异性分别为84%、5/7。CT对胃恶性肿瘤原发病灶诊断敏感性、特异性分别为88.9%和4/5。PET、CT对恶性肿瘤转移淋巴结检测准确率分别为80%和76.5%。PET、CT对远处转移病灶的诊断准确率分别为7/8和2/7。结论:PET对胃恶性肿瘤局部病灶和远处转移病灶检测较为敏感,在临床诊断有较高的应用价值。     

Performance of 2-Deoxy-2-[F-18]fluoro-<Emphasis Type="SmallCaps">d</Emphasis>-glucose Positron Emission Tomography and Integrated PET/CT in Restaged Breast Cancer Patients

PURPOSE: This study was conducted to compare the clinical stage derived from 2-deoxy-2-[F-18]fluoro-D-glucose (FDG) positron emission tomography (PET) to that of integrated PET/computed tomography (CT) in restaged breast cancer patients. PROCEDURES: Fifty-eight female patients (age range 29-80 years, mean age +/-SD, 53.3 +/- 11.7 years) underwent PET/CT restaging for breast cancer. Two experienced nuclear medicine physicians interpreted PET images. A radiologist was added for reading PET/CT studies. A patient-based analysis was performed. Histopathological findings, correlative imaging studies, changes in number, size, and hypermetabolic activity of suspicious lesions and/or patient outcome served as standard of reference for determining the diagnostic accuracy of both modalities. RESULTS: PET staged 79.3% (46/58) of the patients correctly, overstaged seven (12.1%), and understaged five patients (8.6%). Integrated PET/CT staged 89.7% (52/58) of the patients correctly, overstaged four (6.9%), and understaged two patients (3.4%). The staging accuracy of PET/CT was not significantly better than that of PET alone (p = 0.059). Lesions exhibiting mild hypermetabolic activity, benign inflammatory lesions, and physiological variants largely explained incorrect PET findings. CONCLUSION: Integrated PET/CT only marginally improves the restaging accuracy over PET alone (p = 0.059) in breast cancer patients.     

Fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography evaluation of subcutaneous panniculitis-like T cell lymphoma and treatment response

Subcutaneous panniculitis-like T cell lymphoma (SPTCL) is a very rare variant of non-Hodgkin’s lymphoma. Currently, there is no standard imaging method for staging of SPTCL nor for assessment of treatment response. Here, we describe our use of fluorine-18 fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) for staging and monitoring of treatment response in 3 cases of SPTCL. Primary staging by PET/CT showed that all 3 patients had multiple foci in the subcutaneous fat tissue, with SUVmax from 10.5 to 14.6. Involvement of intra-abdominal fat with high SUVmax was identified in 2 of the patients. Use of the triple drug regimen of gemcitabine, cisplatin and methylprednisolone (commonly known as “GEM-P”) as first-line therapy or second-line therapy facilitated complete metabolic response for all 3 cases. FDG PET/CT provides valuable information for staging and monitoring of treatment response and can reveal occult involvement of the intra-abdominal visceral fat. High FDG uptake on pre-treatment PET can identify patients with aggressive disease and help in selection of first-line therapy.     

Positron emission tomography with 2-deoxy-2-[(18)F]fluoro-D-glucose for evaluating local and distant disease in patients with cervical cancer.

PURPOSE: To assess the accuracy of positron emission tomography (PET) with 2-deoxy-2-[(18)F]fluoro-D-glucose (FDG) for evaluating local and distant disease in patients with cervical cancer. METHODS: The PET imaging database maintained at our institution was used to identify patients who received FDG-PET scans for the clinical indication of cervical cancer for the past four years. Patients were followed for a minimum of six months following the PET study. Results of the FDG-PET studies were correlated with surgical pathology, biopsy results, and/or clinical follow up to assess the accuracy of FDG-PET in evaluating local and distant disease. RESULTS: A total of 61 FDG-PET studies performed in 41 patients were included in this retrospective study. Nine FDG-PET studies were performed for initial staging of cervical cancer, and 52 PET scans were performed in 35 different patients as restaging studies following therapy. For the initial staging, the local primary disease was identified in all nine FDG-PET studies, and PET distinguished the patients which had localized disease (four patients) from those with distant metastases on follow-up (five patients) with 100% accuracy. For restaging cervical cancer, FDG-PET had a sensitivity of 0.82 and specificity of 0.97 (accuracy 0.92) for evaluation of local recurrence. For evaluating distant disease in these patients, PET had a sensitivity of 1.00 and specificity of 0.90 (accuracy 0.94). In the evaluation of local disease, focal rectal activity caused false-positive results in two cases. Three false-positive studies for distant disease were caused by inflammatory adenopathy. CONCLUSION: FDG-PET is an accurate modality both for initial staging and restaging of patients with cervical cancer. PET is particularly sensitive for detecting distant metastases, allowing stratification of patients into those with locally confined disease and those with distant disease. These results were achieved by using a standardized PET imaging protocol without the use of bowel preparations, lasix administration, or Foley catheter drainage. Evaluation of local disease can be challenging due to adjacent rectal and bladder activity, and the use of hybrid PET/computed tomography (CT) scanners in the future may further improve evaluation of local disease.     

From 3-D positron emission tomography to 3-D positron emission tomography/computed tomography: what did we learn?

The recent introduction of combined positron emission tomography (PET)/computed tomography (CT) scanners is having a far-reaching effect on the field of medical imaging by bringing functional imaging to the forefront in radiology, oncology and other specialties. The PET/CT scanner is an evolution in technology combining two well-developed imaging modalities: anatomical imaging with CT and functional imaging with PET. The first prototype PET/CT scanner was a consequence of a succession of steps that, in chronological order, included the development of the High Density Avalanche Chamber (HIDAC) PET camera, 3-D PET methodology and the rotating partial-ring tomograph (PRT). The successful completion of each step was a prerequisite to progress to the next phase, and the lessons learned could then be applied to subsequent initiatives. This review will map the milestones from 3-D PET to 3-D PET/CT and assess the role each step played in the development of PET instrumentation over the past two decades.     

2-Deoxy-2-[18F] fluoro-D-glucose uptake in intercostal respiratory muscles on positron emission tomography/computed tomography: smokers versus nonsmokers.

PURPOSE: The purpose of this study was to determine the frequency of 2-deoxy-2-[18F]fluoro-D-glucose (FDG) uptake in the intercostal respiratory muscles (ICM) of smokers versus nonsmokers using positron emission tomography (PET). PROCEDURES: Ninety-six whole-body PET/computed tomography (CT) scans were retrospectively reviewed; 61 studies were from smokers and 35 from nonsmokers. The ICM uptake from the lung apices to the level of the carina was visually scored with respect to FDG intensity as follows: 0 = uptake less than or equal to lung uptake; 1 = greater than lung, but less than mediastinal blood pool; 2 = equal to mediastinal blood pool; and 3 = greater than mediastinal blood pool. RESULTS: In smokers, 30 out of 61 (49.2%) PET/CT scans had uptake that localized to ICM, compared to 3/35 (8.6%) studies in nonsmokers. Average ICM uptake was significantly different between smokers and nonsmokers (0.787 +/- 0.933 and 0.143 +/- 0.494, respectively; P < 0.01). CONCLUSION: Increased FDG uptake in ICM is a physiologic pattern of uptake that is frequently seen and is more common in smokers.     

Clinical applications of positron emission tomography.

Positron emission tomography (PET) has been used extensively as a research tool in the investigation of human physiology and pathology for over a decade. By labelling suitable compounds (for example, glucose, amino acids, ammonia, DOPA or drugs) with positron emitting isotopes which are then administered in tracer amounts, the blood flow, metabolism and even the cell receptor or neurotransmitter distributions may be assessed in vivo. Advances in PET technology and experience now make PET a powerful clinical diagnostic tool, enabling investigation of disease at a molecular level, even in the absence of anatomical abnormalities apparent on computerised tomography (CT) or magnetic resonance imaging (MRI). Clinical PET is already utilised in the management of patients with epilepsy, cerebrovascular and cardiovascular disease, dementia and a wide variety of oncological applications. PET will become more widely available shortly in the UK, with the opening of centres such as the Guy's and St Thomas's Clinical PET Centre in 1992. It will therefore become increasingly important that clinicians are aware of those specific areas in which PET may be the investigation of choice to optimise patient diagnosis, treatment and/or follow-up. This review will endeavour to explain briefly the principles of the PET technique, and then outline those areas where PET has already had an impact on patient management in comparison with the more widely available diagnostic tests, finally outlining promising areas where PET may become more clinically useful in the future.     

Analysis of adrenal masses by 18F-FDG positron emission tomography scanning

This study aimed to analyse the characteristics of adrenal masses visible in the computerised tomography (CT) scans which have been also evaluated by 2-[18F]fluoro-2-deoxy-D-glucose positron emission tomography (18F-FDG PET), and to characterise the features of 18F-FDG PET scans associated with various adrenal endocrine tumours, especially benign functional tumours. 18F-FDG PET scans of 105 patients with adrenal masses on the CT scan were analysed. Positive uptakes in the 18F-FDG PET scans were seen in 60 malignant tumours (54 metastasic lesions, six primary adrenal cancers) and seven benign tumours. The positive predictive value of 18F-FDG PET imaging to characterise an adrenal mass as a malignant tumour was 90%; the corresponding negative predictive value to rule out malignancy was also 90%. Benign adrenal tumours were smaller than that of malignant lesions (p<0.05). The mean standardised uptake value max (SUVmax) of the metastatic lesions [8.4+/-6.5 (microCi/g)/microCi/kg] was significantly higher than that of the benign adrenal tumours [2.4+/-1.2 (microCi/g)/microCi/kg, p<0.001]. Examination of only the primary adrenal lesions revealed that all adrenocortical carcinomas, two of three cases of pheochromocytomas, three of five neuroblastomas and two of four cases of primary aldosteronism showed positive 18F-FDG uptake. In conclusion, for patients presenting adrenal masses with a high probability of malignancy, 18F-FDG PET can be used to differentiate malignant from benign adrenal lesions. However, the 18F-FDG PET uptake did not show an always consistent pattern for endocrine tumours, which was probably due to the variability inherent in 18F-FDG uptake. This study suggests that 18F-FDG PET scanning can offer supporting data to localise and characterise adrenal tumours.     

18F-FLT PET/CT在弥漫大B细胞淋巴瘤诊断及分期中的价值

本研究旨在比较18F-FLT PET/CT与CT对弥漫大B细胞淋巴瘤(DLBCL)的诊断及分期的评估价值,分析DLBCL病灶的18F-FLT PET/CT显像及分布特点。收集2008年9月至2009年12月在本院经病理确诊的36例DLBCL患者,以18F-FLT PET/CT及CT扫描全身及头颅,用18F-FLT PET/CT及CT测量原发肿瘤的部位、大小及SUVmax,计算与主动脉弓血池SUVmax比值(T/MB)。结果表明,18F-FLT PET/CT及CT检测DLBCL病灶的一致率为79.10%,其敏感性分别为96.65%、85.44%,特异性分别为100%、57.14%,阳性预测值分别为100%、96.70%,阴性预测值分别为61.11%、21.05%,假阳性率分别为0%、42.86%,假阴性率分别为3.35%、14.56%,准确率分别为96.82%、83.64%。以上指标组间比较均有统计学差异(P<0.01)。结论:18F-FLT PET/CT对DLBCL检测的敏感性、特异性均明显好于CT,能够协助DLBCL准确分期,18F-FLT与18F-FDG PET/CT显像比较尚待进一步研究证实。     

Mediastinal staging of non-small cell lung carcinoma using computed and positron-emission tomography

BACKGROUND: We evaluated the accuracy of computed tomography (CT) and positron-emission tomography (PET) in the mediastinal staging of non-small cell lung cancer. METHODS: Between May 14, 1999, and November 28, 2000, computerized tomography (CT) and positron-emission tomography (PET) were used to clinically stage 94 consecutive patients with non-small cell carcinoma of the lung (NSCCL). All patients underwent subsequent surgical staging with mediastinoscopy, anterior mediastinotomy, and/or thoracotomy with mediastinal lymphadenectomy. RESULTS: Overall accuracy was the same for both procedures. False-negative results occurred 3 times more often with CT; false-positive results occurred twice as often with PET. Sensitivity and specificity were 64% and 94%, respectively, for CT, versus 88% and 86%, respectively, for PET. Positive and negative predictive values were 80% and 88%, respectively, for CT, versus 71% and 95%, respectively, for PET. CONCLUSION: In addition to routine use of CT, PET seems to achieve high negative predictive value in the evaluation of mediastinal disease; PET seems particularly helpful in assessing absence of tumor in bulky nodes after neoadjuvant chemotherapy and/or radiotherapy.     

The utility of 2-deoxy-2-[18F]fluoro-D-glucose-positron emission tomography and combined positron emission tomography and computed tomography in lymphoma and melanoma.

The purpose of this article is to review the clinical utility of FDG and FDG PET/CT imaging in lymphoma and melanoma. A review of the important articles supporting the use of FDG PET imaging in the staging, restaging, and monitoring of response to therapy in lymphoma and melanoma is provided. The intent is to give the nuclear medicine physician and or radiologist the perspective of what may be important clinically to make FDG PET imaging an integral part of the workup of lymphoma and melanoma patients. Specific clinical scenarios and uptake patterns that are unique for lymphoma and melanoma are discussed to ensure relevant and proper interpretation of the FDG PET scans. FDG PET scanning in summary is a useful imaging modality in the staging, restaging, and response evaluation of patients with lymphoma and melanoma.     

Whole-body magnetic resonance imaging and positron emission tomography-computed tomography in oncology

The advent of positron emission tomography-computed tomography (PET-CT) and whole-body magnetic resonance imaging (WB-MRI) has introduced tumor imaging with a systemic and functional approach compared with established sequential, multimodal diagnostic algorithms.Whole-body PET with [18F]-fluoro-2-desoxy-glucose is a useful imaging procedure for tumor staging and monitoring that can visualize active tumor tissue by detecting pathological glucose metabolism. The combination of PET with the detailed anatomical information of multislice computed tomography as dual-modality scanners has markedly increased lesion localization and diagnostic accuracy compared with both modalities as standalone applications.Hardware innovations, such as the introduction of multi-receiver channel whole-body MRI scanners at 1.5 and, recently, 3 T, combined with acquisition acceleration techniques, have made high-resolution WB-MRI clinically feasible. Now, a dedicated assessment of individual organs with various soft tissue contrast, spatial resolution, and contrast media dynamics can be combined with whole-body anatomical coverage in a multiplanar imaging approach. More flexible protocols (eg, T1-weighted turbo spin-echo and short inversion recovery imaging, dedicated lung imaging or dynamic contrast-enhanced studies of the abdomen) can be performed within 45 minutes.Whole-body magnetic resonance imaging has recently been proposed for tumor screening of asymptomatic individuals, and potentially life-changing diagnoses, such as formerly unknown malignancy, have been reported. However, larger patient cohort studies will have to show the cost efficiency and the clinical effectiveness of such an approach.For initial tumor staging, PET-CT has proved more accurate for the definition of T-stage and lymph node assessment, mainly because of the missing metabolic information in WB-MRI. However, new applications, such as magnetic resonance whole-body diffusion-weighted imaging or lymphotropic contrast agents, may significantly increase sensitivity in near future. Whole-body magnetic resonance imaging has shown advantages for the detection of distant metastatic disease, especially from tumors frequently spreading to the liver or brain and as a whole-body bone marrow screening application. Within this context, WB-MRI is highly accurate for the detection of skeletal metastases and staging of multiple myeloma. This article summarizes recent developments of CT/PET-CT and WB-MRI and highlights their performance within the scope of systemic oncological imaging.     

Positron emission tomographic scans in lymphoma: convention and controversy

The use of sensitive and specific imaging techniques for accurate initial staging and evaluation of response to therapy in patients with lymphoma is essential for their optimal management. Fluorine 18 fluorodeoxyglucose (FDG) positron emission tomography (PET) integrated with computed tomography (CT) has emerged as a powerful imaging tool and is being routinely used in staging, response evaluation, and posttreatment surveillance in patients with non-Hodgkin lymphoma and Hodgkin lymphoma. PET/CT is currently widely used in clinical practice, but the established clinical benefit is currently restricted to the posttreatment evaluation of Hodgkin lymphoma, diffuse large B-cell lymphoma, and follicular lymphoma. Although used in other histologic subtypes and in other clinical situations including response assessment, its impact on patient outcome remains to be demonstrated. We performed a literature search of PubMed from 1999 to 2011 using the following keywords: PET scan, FDG-PET, PET/CT, lymphoma. This review addresses the challenges and controversies in the use of PET/CT scans in the management of patients with lymphoma.     

Comparison of bone and 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography in the evaluation of bony metastases in lung cancer.

Positron emission tomography (PET) is a proven accurate modality used for the detection of active malignant tumors. The performance of PET in detecting bony metastases, however, has not been adequately investigated. PURPOSE: The aim of this study was to compare the performance of bone and 2-deoxy-2-[18F]fluoro-D-glucose (FDG) PET scans in evaluating bony metastases from lung cancer. PROCEDURE: This retrospective study evaluated 85 patients with lung cancer who underwent both FDG-PET and bone scans within three weeks of each other for initial staging or restaging. The number and sites of bony lesions on FDG-PET and bone scans were correlated. Concordant lesions between the two modalities were considered to be positive for malignancy; discordant lesions were compared with X-rays, computed tomography (CT), magnetic resonance imaging (MRI), and/or follow-up findings. The mean follow-up interval was 7.9 months. RESULTS: Bone scans were positive for lesions in 24 patients and negative in 61 patients while FDG-PET was positive for bony lesions in 17 patients and negative in 65 patients. FDG-PET was indeterminate for rib involvement in three patients having an underlying lung cancer, whom were evaluated separately. A total of 88 and 41 bony lesions were identified on bone scans and FDG-PET, respectively. Correlation of bone scans with other imaging modalities and clinical follow-up findings revealed a sensitivity, specificity, positive and negative predictive value of 81%, 78%, 34%, and 93%, respectively and for FDG-PET 73% (P=0.81), 88% (P=0.03), 46% (P=0.5,) and 97% (P=0.04), respectively. Using bone scans, 10 patients were correctly diagnosed with bony metastases, 54 were correctly diagnosed free of bony metastases, 17 patients were falsely diagnosed with metastases, and metastases were missed in one patient. Using FDG-PET scans, eight patients were correctly diagnosed with bony metastases, 66 were correctly diagnosed free of bony metastases, seven patients were falsely diagnosed with metastases, and one patient had metastases which were missed. Of the three patients with lung cancer close to the chest wall in whom FDG-PET was indeterminate for rib involvement, the bone scans were truly positive for rib involvement in two of them, and truly negative in the remaining patient. CONCLUSIONS: FDG-PET scans demonstrated significantly higher specificity and negative predictive values than bone scans for evaluating bony metastases from lung cancer. On the other hand, bone scans are more sensitive with higher positive predictive values than FDG-PET scans, but the differences were not statistically significant.     

Recurrent pancreatic carcinoma and cholangiocarcinoma: <Superscript>18</Superscript>F-fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT)

Although the current literature is limited, available data suggest that ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) imaging improves the evaluation of patients with recurrent pancreatic carcinoma and cholangiocarcinoma. There is evidence that PET/CT is particularly useful in the setting of elevated tumor markers and negative or equivocal CT findings. This article reviews the nature of these carcinomas in the post-therapy setting and describes the strengths and limitations of PET/CT when used for monitoring recurrence.     

（18）F-FDDNP脑正电子发射计算机断层显像鉴别阿尔茨海默病与血管性痴呆

背景:目前,一些神经影像学检测方法如MRI、功能磁共振、18F-FDG正电子发射计算机断层显像(PET)对阿尔茨海默病的诊断均有帮助,但并不特异。18F-FDDNP是β淀粉样蛋白的特殊标记物,故应用18F-FDDNPPET有可能早期诊断阿尔茨海默病。目的:探讨18F-FDDNPPET脑显像在阿尔茨海默病诊断中的价值,建立阿尔茨海默病患者早期诊断的可靠临床影像学指标。设计:对照分析。单位:解放军总医院老年神经内科和核医学科。对象:受试者来自2004-05/2005-03解放军总医院就诊的患者,检查前均签署知情同意书。①阿尔茨海默病组:7例,年龄(74.88±12.03)岁,诊断符合美国国立神经病语言障碍卒中研究所/阿尔茨海默病及相关疾病协会标准和精神疾病诊断和统计手册第四版修订本(DSM-IV)标准,颅脑CT或MRI显示颞叶钩回间距≥30mm。②血管性痴呆组:6例,年龄(73.83±4.75)岁,诊断符合美国国立神经系统疾病与卒中研究所及DSM-IV标准,颞叶钩回间距均<30mm。③对照组:6例,年龄(71.17±3.71)岁,无脑白质疏松,智能检查均正常。方法:所有受试者行PET显像。PET扫描仪型号为SIEMENSECATEXACTHR,示踪剂选用18F-FDDNP(放射化学纯度>95%,放射性活度测量误差<10%)。受试者分别在药物注射后5,25和45min采集图像,重建后得到脑水平位、冠状位各断层图像。主要观察指标:各组受试者18F-FDDNPPET脑成像特点。结果:①对照组:脑未见明显萎缩征象,给药45min左右时皮质及皮质下核团放射性均已基本清除,脑结构分辨不清。②血管性痴呆组:可见脑萎缩,脑室系统有不同程度扩大。3个时段放射性清除情况与对照组较为近似。③阿尔茨海默病组:脑萎缩明显,脑室系统扩大。3个时段放射性清除情况与其他2组图像有明显的不同,皮质及海马部位放射性清除较慢,至药物注射45min时仍可清晰区分脑灰质与白质部分,皮质及海马部位可见较多放射性滞留。结论:18F-FDDNPPET脑显像能够鉴别阿尔茨海默病和血管性痴呆,是阿尔茨海默病诊断的一个有效的影像学指标。