Utility of Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography in Patients with Fever of Unknown Origin Diagnosed as Lymphoma

Objective

To assess the efficacy of fluorine-18 fluorodeoxyglucose positron emission tomography (¹⁸F-FDG PET)/computed tomography (CT) in the diagnosis of patients with fever of unknown origin (FUO), who were finally diagnosed as lymphoma.

Subjects and Methods

A retrospective study was performed in the First Affiliated Hospital, School of Medicine of Zhejiang University, China, from March 2009 to March 2012. The PET/CT images of consecutive patients with FUO were analyzed. Within 1 week of PET/CT scanning, additional histological tests were also performed if clinically needed.

Results

A total of 73 consecutive patients were included. Of these, 34 (47s%) had a PET/CT finding suggestive of the presence of lymphoma and 29 (85s%) had a diagnosis of confirmed lymphoma; 39 (53s%) had a PET/CT result revealing the absence of lymphoma and 4 (10s%) were diagnosed by biopsy as having lymphoma. The most frequent lymphoma diagnosis was peripheral T cell lymphoma (n = 16; 55s%), followed by diffuse large B cell lymphoma (n = 9; 31s%). The accuracy of PET/CT was 88s%.

Conclusion

In this study, PET/CT had high diagnostic accuracy in patients with FUO resulting from lymphoma, which indicated that PET/CT scanning was a valuable diagnostic tool for these groups of patients with FUO.Key Words: Fever of unknown origin, Positron emission tomography, Computed tomography, Diagnosis, Lymphoma     

胰高血糖素样肽-1受体PET/CT定位诊断胰岛素瘤的技术规范

胰岛素瘤的诊断和手术治疗依赖于准确的影像学检查定位。以胰腺β细胞为靶点的胰高血糖素样肽-1受体(glucagon-like peptide-1 receptor, GLP-1R)是近年来胰岛素瘤影像研究中的亮点, 推荐临床推广使用⁶⁸Ga-exendin-4进行GLP-1R正电子发射断层显像/计算机体层成像(positron emission tomography/computed tomography, PET/CT)来定位诊断胰岛素瘤。本文介绍GLP-1R显像在胰岛素瘤中的应用概况, 并以⁶⁸Ga-exendin-4 GLP-1R PET/CT显像为例, 介绍该技术的操作规范, 以期为临床提供借鉴。     

Pediatric Positron Emission Tomography–Computed Tomography Protocol Considerations

Pediatric body oncology positron emission tomography-computed tomography studies require special considerations for optimal diagnostic performance while limiting radiation exposure to young patients. Differences from routine adult procedures include the patient preparation phase, radiopharmaceutical dose, computed tomography acquisition parameters, and approach to computed tomography contrast materials and imaging sequence. Attention to these differences define the best practice for positron emission tomography-computed tomography examinations of children with cancer contributing to optimal care of these patients.     

Protocol Considerations for Thoracic Positron Emission Tomography–Computed Tomography

The rapid technological advances of positron emission tomography-computed tomography (PET-CT) have introduced many new possibilities and questions as to how best to utilize and perform 2-deoxy-2-[F-18]fluoro-D-glucose (FDG) PET-CT for maximum clinical benefit. The focus of this discussion is the tailoring of PET-CT protocols, emphasizing the incorporation of optimized (diagnostic) CT techniques, for adult thoracic oncologic indications. Many of the protocol strategies described, particularly those involving breath-hold and contrast-enhanced CT, are based on the author's experience in a busy private practice PET-CT center, prior to a recent transition to an academic practice.     

18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography Following Chimeric Antigen Receptor T-cell Therapy in Large B-cell Lymphoma

Molecular Imaging and Biology - 18F-Fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) is a well-established imaging modality to assess responses in patients with...     

正电子发射计算机断层技术在针刺临床中的应用进展

正电子发射计算机断层(PET)是当前核医学领域最先进的技术之一.本文综述了近几年PET技术在针刺临床治疗不同疾病中的应用进展.     

Cardiac Positron Emission Tomography: a Clinical Perspective

Cardiac positron emission tomography is a powerful, quantitative, non-invasive imaging modality, which adds valuable diagnostic and prognostic information to the clinical work-up. Myocardial perfusion and viability imaging are, as a result of continuously growing evidence, established clinical indications that may be cost-effective, due to the high diagnostic accuracy of cardiac positron emission tomography, despite high single-test costs. In the field of inflammation imaging, new indications are entering the clinical arena, which may contribute to a better diagnosis and overall patient care, as for instance in patients with cardiac sarcoidosis, prosthetic valve endocarditis and cardiac device infections. This review will discuss the individual strengths and weaknesses of cardiac positron emission tomography and, hence, the resulting clinical usefulness based on the current evidence for an individualized, patient-centered imaging approach.     

Clinical Practice Guidelines for the Utilization of Positron Emission Tomography/Computed Tomography Imaging in Selected Oncologic Applications: Suggestions from a Provider Group

Purpose Positron emission tomography, combined with computed tomography (PET/CT) has provided clinicians with useful information regarding the diagnosis, initial staging, restaging, and therapy monitoring of malignancies since the beginning of the current century. Our intent here is to identify the critical steps in clinical workups and follow-up, in the true outpatient clinical setting of a freestanding imaging center, for utilization of PET/CT in four different cancer types. Methods The four most common reasons for referrals to our facility were identified by reviewing two years of referral data. They were lung cancer (including solitary pulmonary nodule), lymphomas, breast cancer, and colorectal cancer. A review of published literature from 1996 and later was accepted as evidence of appropriateness for utilizing PET/CT in various clinical scenarios. In addition, a medical advisory board consisting of 15 referring physicians representing various specialties was established to provide practical advice regarding the appropriate use of PET/CT in clinical situations. National Comprehensive Cancer Network (NCCN) guidelines were also referenced to establish a baseline for clinical workups at various stages of disease. Results Several inconsistencies were identified among the three primary sources of information leading to the establishment of a standardized algorithm for each cancer type. NCCN data did not always agree with published literature, which was also often different from actual clinical practices of referring physicians. The most common inconsistencies included differing opinions from the referrers vs what was published in the NCCN guidelines, especially with regard to the utilization of PET/CT for applications not yet covered by insurance companies. After a reconciliation of the medical advisory board’s clinical practices and several published articles, a consensus was established by the medical advisory board for the use of PET/CT imaging for the four cancer types, enabling us to identify the appropriate timing of PET/CT utilization in patient work-ups. Conclusions A PET/CT-centric clinical practice decision tree algorithm can be established by assessing a variety of sources of information. Although published literature and NCCN guidelines offer validated guidance to appropriateness, and third party insurance payors have established their own appropriateness standards, our experience showed that inclusion of practical experience from referring physicians who frequently utilize PET/CT imaging provided additional, useful input.     

正电子发射计算机断层显像在脑梗死治疗中的应用进展

脑梗死系由各种原因所致的局部脑组织血液供应障碍,导致脑组织缺血缺氧性病变坏死,进而产生临床上对应的神经功能缺失表现。本文对正电子发射计算机断层显像在脑梗死治疗中的应用进行总结。     

Optimizing Dual-Time and Serial Positron Emission Tomography and Single Photon Emission Computed Tomography Scans for Diagnoses and Therapy Monitoring

INTRODUCTION: A region's early and late tracer uptake activities, QE and QL, within a dual-time scan (i.e. using two frames) or in serial scans (as for monitoring therapeutic response), are popular quantitative diagnostic aids, especially in oncology. In this paper, maximum performance is sought from their joint use. METHODS: QL/QnE is introduced as a tumor marker with an empirical n. This generalizes traditional data weighting having n=1 for QL/QE, the retention index (RI), with its associated % difference. Using patient data, iterative guessing finds an optimal n that maximizes a measure of diagnostic performance: D=(difference of normal and abnormal marker means)/(their combined SD), which may be computed from values of QL/QnE, as well as of QL, QE, and RI each used alone. For 2-deoxy-2-[F-18]fluoro-D-glucose(FDG)-positron emission tomography (PET) dual-time protocols, another approach to optimization-selection of scan times-is investigated by simulations using the Sokolov model. RESULTS: A meta-analysis of 12 PET and single photon emission computed tomography (SPECT) studies with various tracers, cancers, and scan classes (dual-time or serial) finds ns from 0.5 to 1.1. The optimal D necessarily exceeds the best (or any) computed using QE, QL, or RI: negligibly to by as much as 0.6 (or 1.5). The increases in optimal receiver operating curve area (Az) over the best (or any) traditional marker range from negligible to 0.07 (or 0.4). QE alone usually has the lowest D and Az. Statistically significant performance improvement of QL/QnE over QE and QL is shown for most studies. Contrasting with an optimal n, another value n0 can also be found where D=0. Occasionally, n0 can be close to 1, and RI then will have a small D and poor performance. Simulation with kinetic modeling of FDG dual-time scans for liver and liver metastases demonstrates worst and best scan times. Indicated for these imaging protocols are QE at very early cellular transport associated times and QL rather late when phosphorylation/dephosphorylation dominate. Benefits from choosing optimal times in dual-time protocols, especially in combination with choosing optimal ns, can be significant. CONCLUSION: A protocol-dependent optimizing parameter n in an improved classification marker can easily be identified in a learning set of scans having normals and abnormals. Finding this parameter below 1.0 in most all studies suggests that a popularly used QL/QE may often overweight early activities. Additionally, QL/QE may sometimes be a poor marker choice and underestimate a protocol's diagnostic capability. Subsequent use of the proposed QL/QnE in settings similar to that of the learning set gives improved diagnostic performance over traditional approaches, although by widely varying amounts. Additionally, a method of seeking optimal scan times is demonstrated and suggests significant gains in dual-time protocol performances are possible.     

Single-photon Emission Tomography/Computed Tomography Delineation of Freiberg Infraction

The role of nuclear medicine diagnostic bone scanning is well established and the influence of coregistration between single-photon emission computed tomography and computed tomography well documented. This case provides an insight into a less frequently encountered pathology in which the combination of single-photon emission computed tomography and computed tomography permitted the differentiation of potential pathology.